diff --git a/prism/src/mtbdd/PM_ProbReachReward.cc b/prism/src/mtbdd/PM_ProbReachReward.cc
index d3fb397b..fd1085c9 100644
--- a/prism/src/mtbdd/PM_ProbReachReward.cc
+++ b/prism/src/mtbdd/PM_ProbReachReward.cc
@@ -105,13 +105,18 @@ jlong __jlongpointer m	// 'maybe' states
 	sol = NULL;
 	switch (lin_eq_method) {
 		case LIN_EQ_METHOD_POWER:
-			sol = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1Power(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(state_rewards), ptr_to_jlong(state_rewards), false)); break;
+			sol = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1Power(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(state_rewards), ptr_to_jlong(state_rewards), false));
+			break;
 		case LIN_EQ_METHOD_JACOBI:
-			sol = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JOR(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(state_rewards), ptr_to_jlong(state_rewards), false, 1.0)); break;
+			sol = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JOR(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(state_rewards), ptr_to_jlong(state_rewards), false, 1.0));
+			break;
 		case LIN_EQ_METHOD_JOR:
-			sol = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JOR(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(state_rewards), ptr_to_jlong(state_rewards), false, lin_eq_method_param)); break;
+			sol = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JOR(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(state_rewards), ptr_to_jlong(state_rewards), false, lin_eq_method_param));
+			break;
 		default:
-			PM_SetErrorMessage("Gauss-Seidel and its variants are currently not supported by the MTBDD engine"); return 0;
+			// set error message and return NULL pointer after cleanup, below
+			PM_SetErrorMessage("Gauss-Seidel and its variants are currently not supported by the MTBDD engine");
+			break;
 	}
 	
 	// set reward for infinity states to infinity
diff --git a/prism/src/mtbdd/PM_ProbReachRewardInterval.cc b/prism/src/mtbdd/PM_ProbReachRewardInterval.cc
index 1793faf6..4eee082e 100644
--- a/prism/src/mtbdd/PM_ProbReachRewardInterval.cc
+++ b/prism/src/mtbdd/PM_ProbReachRewardInterval.cc
@@ -120,13 +120,18 @@ jint flags
 	sol = NULL;
 	switch (lin_eq_method) {
 		case LIN_EQ_METHOD_POWER:
-			sol = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1PowerInterval(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(state_rewards), ptr_to_jlong(lower), ptr_to_jlong(upper), false, flags)); break;
+			sol = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1PowerInterval(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(state_rewards), ptr_to_jlong(lower), ptr_to_jlong(upper), false, flags));
+			break;
 		case LIN_EQ_METHOD_JACOBI:
-			sol = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JORInterval(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(state_rewards), ptr_to_jlong(lower), ptr_to_jlong(upper), false, 1.0, flags)); break;
+			sol = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JORInterval(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(state_rewards), ptr_to_jlong(lower), ptr_to_jlong(upper), false, 1.0, flags));
+			break;
 		case LIN_EQ_METHOD_JOR:
-			sol = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JORInterval(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(state_rewards), ptr_to_jlong(lower), ptr_to_jlong(upper), false, lin_eq_method_param, flags)); break;
+			sol = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JORInterval(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(state_rewards), ptr_to_jlong(lower), ptr_to_jlong(upper), false, lin_eq_method_param, flags));
+			break;
 		default:
-			PM_SetErrorMessage("Gauss-Seidel and its variants are currently not supported by the MTBDD engine"); return 0;
+			// set error message and return NULL pointer after cleanup, below
+			PM_SetErrorMessage("Gauss-Seidel and its variants are currently not supported by the MTBDD engine");
+			break;
 	}
 	
 	// set reward for infinity states to infinity
diff --git a/prism/src/mtbdd/PM_ProbUntil.cc b/prism/src/mtbdd/PM_ProbUntil.cc
index 1650468a..5bd86540 100644
--- a/prism/src/mtbdd/PM_ProbUntil.cc
+++ b/prism/src/mtbdd/PM_ProbUntil.cc
@@ -85,13 +85,18 @@ jlong __jlongpointer m	// 'maybe' states
 	soln = NULL;
 	switch (lin_eq_method) {
 		case LIN_EQ_METHOD_POWER:
-			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1Power(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(b), false)); break;
+			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1Power(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(b), false));
+			break;
 		case LIN_EQ_METHOD_JACOBI:
-			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JOR(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(b), false, 1.0)); break;
+			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JOR(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(b), false, 1.0));
+			break;
 		case LIN_EQ_METHOD_JOR:
-			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JOR(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(b), false, lin_eq_method_param)); break;
+			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JOR(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(b), false, lin_eq_method_param));
+			break;
 		default:
-			PM_SetErrorMessage("Gauss-Seidel and its variants are currently not supported by the MTBDD engine"); return 0;
+			// set error message and return NULL pointer after cleanup, below
+			PM_SetErrorMessage("Gauss-Seidel and its variants are currently not supported by the MTBDD engine");
+			break;
 	}
 	
 	// free memory
diff --git a/prism/src/mtbdd/PM_ProbUntilInterval.cc b/prism/src/mtbdd/PM_ProbUntilInterval.cc
index 52d33a78..c1ace0da 100644
--- a/prism/src/mtbdd/PM_ProbUntilInterval.cc
+++ b/prism/src/mtbdd/PM_ProbUntilInterval.cc
@@ -104,13 +104,18 @@ jint flags
 	soln = NULL;
 	switch (lin_eq_method) {
 		case LIN_EQ_METHOD_POWER:
-			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1PowerInterval(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(lower), ptr_to_jlong(upper), false, flags)); break;
+			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1PowerInterval(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(lower), ptr_to_jlong(upper), false, flags));
+			break;
 		case LIN_EQ_METHOD_JACOBI:
-			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JORInterval(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(lower), ptr_to_jlong(upper), false, 1.0, flags)); break;
+			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JORInterval(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(lower), ptr_to_jlong(upper), false, 1.0, flags));
+			break;
 		case LIN_EQ_METHOD_JOR:
-			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JORInterval(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(lower), ptr_to_jlong(upper), false, lin_eq_method_param, flags)); break;
+			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JORInterval(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(lower), ptr_to_jlong(upper), false, lin_eq_method_param, flags));
+			break;
 		default:
-			PM_SetErrorMessage("Gauss-Seidel and its variants are currently not supported by the MTBDD engine"); return 0;
+			// set error message and return NULL pointer after cleanup, below
+			PM_SetErrorMessage("Gauss-Seidel and its variants are currently not supported by the MTBDD engine");
+			break;
 	}
 	
 	// free memory
diff --git a/prism/src/mtbdd/PM_StochSteadyState.cc b/prism/src/mtbdd/PM_StochSteadyState.cc
index 0d30316f..9c25d398 100644
--- a/prism/src/mtbdd/PM_StochSteadyState.cc
+++ b/prism/src/mtbdd/PM_StochSteadyState.cc
@@ -101,13 +101,18 @@ jint num_cvars
 	soln = NULL;
 	switch (lin_eq_method) {
 		case LIN_EQ_METHOD_POWER:
-			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1Power(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(init), true)); break;
+			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1Power(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(init), true));
+			break;
 		case LIN_EQ_METHOD_JACOBI:
-			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JOR(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(init), true, 1.0)); break;
+			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JOR(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(init), true, 1.0));
+			break;
 		case LIN_EQ_METHOD_JOR:
-			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JOR(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(init), true, lin_eq_method_param)); break;
+			soln = jlong_to_DdNode(Java_mtbdd_PrismMTBDD_PM_1JOR(env, cls, ptr_to_jlong(odd), ptr_to_jlong(rvars), num_rvars, ptr_to_jlong(cvars), num_cvars, ptr_to_jlong(a), ptr_to_jlong(b), ptr_to_jlong(init), true, lin_eq_method_param));
+			break;
 		default:
-			PM_SetErrorMessage("Gauss-Seidel and its variants are currently not supported by the MTBDD engine"); return 0;
+			// set error message and return NULL pointer after cleanup, below
+			PM_SetErrorMessage("Gauss-Seidel and its variants are currently not supported by the MTBDD engine");
+			break;
 	}
 	
 	// normalise