diff --git a/source/glest_game/ai/ai_rule.cpp b/source/glest_game/ai/ai_rule.cpp
index f8815c41..f4d67ed1 100644
--- a/source/glest_game/ai/ai_rule.cpp
+++ b/source/glest_game/ai/ai_rule.cpp
@@ -1090,10 +1090,10 @@ void AiRuleProduce::produceSpecific(const ProduceTask *pt){
 							defCt = producersDefaultCommandType[bestIndex][bestCommandTypeIndex];
 						}
 
-						if(ai->outputAIBehaviourToConsole()) printf("mega #2 produceSpecific giveCommand to unit [%s] commandType [%s]\n",aiInterface->getMyUnit(bestIndex)->getType()->getName().c_str(),defCt->getName().c_str());
+						if(ai->outputAIBehaviourToConsole()) printf("mega #2 produceSpecific giveCommand to unit [%s] commandType [%s]\n",aiInterface->getMyUnit(bestIndex)->getType()->getName().c_str(),(defCt != NULL ? defCt->getName().c_str() : "n/a"));
 						if(aiInterface->isLogLevelEnabled(4) == true) {
 							char szBuf[8096]="";
-							snprintf(szBuf,8096,"mega #2 produceSpecific giveCommand to unit [%s] commandType [%s]",aiInterface->getMyUnit(bestIndex)->getType()->getName().c_str(),defCt->getName().c_str());
+							snprintf(szBuf,8096,"mega #2 produceSpecific giveCommand to unit [%s] commandType [%s]",aiInterface->getMyUnit(bestIndex)->getType()->getName().c_str(),(defCt != NULL ? defCt->getName().c_str() : "n/a"));
 							aiInterface->printLog(4, szBuf);
 						}
 						aiInterface->giveCommand(bestIndex, defCt);
@@ -1114,10 +1114,10 @@ void AiRuleProduce::produceSpecific(const ProduceTask *pt){
 							defCt = producersDefaultCommandType[bestIndex][bestCommandTypeIndex];
 						}
 
-						if(ai->outputAIBehaviourToConsole()) printf("mega #3 produceSpecific giveCommand to unit [%s] commandType [%s]\n",aiInterface->getMyUnit(bestIndex)->getType()->getName().c_str(),defCt->getName().c_str());
+						if(ai->outputAIBehaviourToConsole()) printf("mega #3 produceSpecific giveCommand to unit [%s] commandType [%s]\n",aiInterface->getMyUnit(bestIndex)->getType()->getName().c_str(),(defCt != NULL ? defCt->getName().c_str() : "n/a"));
 						if(aiInterface->isLogLevelEnabled(4) == true) {
 							char szBuf[8096]="";
-							snprintf(szBuf,8096,"mega #3 produceSpecific giveCommand to unit [%s] commandType [%s]",aiInterface->getMyUnit(bestIndex)->getType()->getName().c_str(),defCt->getName().c_str());
+							snprintf(szBuf,8096,"mega #3 produceSpecific giveCommand to unit [%s] commandType [%s]",aiInterface->getMyUnit(bestIndex)->getType()->getName().c_str(),(defCt != NULL ? defCt->getName().c_str() : "n/a"));
 							aiInterface->printLog(4, szBuf);
 						}
 
@@ -1134,10 +1134,10 @@ void AiRuleProduce::produceSpecific(const ProduceTask *pt){
 
 						defCt = producersDefaultCommandType[bestIndex][bestCommandTypeIndex];
 					}
-					if(ai->outputAIBehaviourToConsole()) printf("mega #4 produceSpecific giveCommand to unit [%s] commandType [%s]\n",aiInterface->getMyUnit(bestIndex)->getType()->getName().c_str(),defCt->getName().c_str());
+					if(ai->outputAIBehaviourToConsole()) printf("mega #4 produceSpecific giveCommand to unit [%s] commandType [%s]\n",aiInterface->getMyUnit(bestIndex)->getType()->getName().c_str(),(defCt != NULL ? defCt->getName().c_str() : "n/a"));
 					if(aiInterface->isLogLevelEnabled(4) == true) {
 						char szBuf[8096]="";
-						snprintf(szBuf,8096,"mega #4 produceSpecific giveCommand to unit [%s] commandType [%s]",aiInterface->getMyUnit(bestIndex)->getType()->getName().c_str(),defCt->getName().c_str());
+						snprintf(szBuf,8096,"mega #4 produceSpecific giveCommand to unit [%s] commandType [%s]",aiInterface->getMyUnit(bestIndex)->getType()->getName().c_str(),(defCt != NULL ? defCt->getName().c_str() : "n/a"));
 						aiInterface->printLog(4, szBuf);
 					}
 
diff --git a/source/glest_game/main/program.cpp b/source/glest_game/main/program.cpp
index b85d7d53..0b23487a 100644
--- a/source/glest_game/main/program.cpp
+++ b/source/glest_game/main/program.cpp
@@ -617,6 +617,9 @@ void Program::setState(ProgramState *programStateNew, bool cleanupOldState) {
 
 		this->programState= programStateNew;
 		assert(programStateNew != NULL);
+		if(programStateNew == NULL) {
+			throw megaglest_runtime_error("programStateNew == NULL");
+		}
 		programStateNew->load();
 
 		if(SystemFlags::getSystemSettingType(SystemFlags::debugSystem).enabled) SystemFlags::OutputDebug(SystemFlags::debugSystem,"In [%s::%s Line: %d]\n",extractFileFromDirectoryPath(__FILE__).c_str(),__FUNCTION__,__LINE__);
diff --git a/source/glest_game/world/unit_updater.cpp b/source/glest_game/world/unit_updater.cpp
index e839f794..9d925734 100644
--- a/source/glest_game/world/unit_updater.cpp
+++ b/source/glest_game/world/unit_updater.cpp
@@ -1772,7 +1772,7 @@ void UnitUpdater::updateRepair(Unit *unit, int frameIndex) {
     if(SystemFlags::getSystemSettingType(SystemFlags::debugUnitCommands).enabled) SystemFlags::OutputDebug(SystemFlags::debugUnitCommands,"In [%s::%s Line: %d] rct = %p\n",__FILE__,__FUNCTION__,__LINE__,rct);
 
 	Unit *repaired = (command != NULL ? map->getCell(command->getPos())->getUnitWithEmptyCellMap(fLand) : NULL);
-	if(repaired == NULL) {
+	if(repaired == NULL && command != NULL) {
 		repaired = map->getCell(command->getPos())->getUnit(fLand);
 	}
 
@@ -1891,6 +1891,10 @@ void UnitUpdater::updateRepair(Unit *unit, int frameIndex) {
 	if(unit->getCurrSkill()->getClass() != scRepair ||
 		(nextToRepaired == false && peerUnitBuilder == NULL)) {
 
+		if(command == NULL) {
+			throw megaglest_runtime_error("command == NULL");
+		}
+
 		Vec2i repairPos = command->getPos();
 		bool startRepairing = (repaired != NULL && rct->isRepairableUnitType(repaired->getType()) && repaired->isDamaged());