do not allow closing the "how to proceed after unfinished run detected" dialog...

do not allow closing the "how to proceed after unfinished run detected" dialog without giving an answer by just reopening it!
closes #108

Source/StudyFrameworkPlugin/Private/SFGameInstance.cpp

@@ -246,8 +246,17 @@ void USFGameInstance::PrepareWithStudySetup(ASFStudySetup* Setup)
 			"Next Participant",
 			"Restart Study"
 		};
+
+
+		bool bValidDecision = false;
+		while (!bValidDecision) {
 			int Answer = FSFUtils::OpenCustomDialog(MessageTitle, MessageText, Buttons);
 
+			if (Answer < 0) {
+				FSFLoggingUtils::Log("[USFGameInstance::PrepareWithStudySetup] The window for deciding on how to recover from an unfinished run was closed without giving an answer, repeat question!", false);
+				continue;
+			}
+
 			switch (Answer)
 			{
 			case 2:
@@ -256,21 +265,25 @@ void USFGameInstance::PrepareWithStudySetup(ASFStudySetup* Setup)
 				Conditions = StudySetup->GetAllConditionsForRun(ParticipantSequenceNumber);
 				//clear data
 				USFParticipant::ClearLogData(Setup);
+				bValidDecision = true;
 				break;
 			case 0:
 				FSFLoggingUtils::Log("[USFGameInstance::PrepareWithStudySetup]: Continue last participant");
 				Conditions = USFParticipant::GetLastParticipantsConditions();
 				StartCondition = Conditions[USFParticipant::GetLastParticipantLastConditionStarted()];
 				bRecoverParticipantData = true;
+				bValidDecision = true;
 				break;
 			case 1:
 				FSFLoggingUtils::Log("[USFGameInstance::PrepareWithStudySetup]: Continue with the next participant");
 				ParticipantSequenceNumber++;
 				Conditions = StudySetup->GetAllConditionsForRun(ParticipantSequenceNumber);
+				bValidDecision = true;
 				break;
 			default:;
 			}
 		}
+	}
 
 	if (StudySetup->bPreloadAllMapsOnStart)
 	{