diff --git a/CMakeLists.txt b/CMakeLists.txt
index c4574ce0..d7607e74 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -40,6 +40,7 @@ ELSEIF(MINGW)
       SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=gnu++11 -Wall")
 ENDIF()
 
+SET(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -Werror=return-type")
 ################################ 3rd Party Libs ################################
 
 # Find the required Qt parts
diff --git a/gui/MainWindow.cpp b/gui/MainWindow.cpp
index 65db066b..60b64cb9 100644
--- a/gui/MainWindow.cpp
+++ b/gui/MainWindow.cpp
@@ -757,7 +757,7 @@ void MainWindow::on_actionAddInstance_triggered()
 	auto &loader = InstanceFactory::get();
 
 	auto error = loader.createInstance(newInstance, newInstDlg.selectedVersion(), instDir);
-	QString errorMsg = QString("Failed to create instance %1: ").arg(instDirName);
+	QString errorMsg = tr("Failed to create instance %1: ").arg(instDirName);
 	switch (error)
 	{
 	case InstanceFactory::NoCreateError:
@@ -768,21 +768,21 @@ void MainWindow::on_actionAddInstance_triggered()
 
 	case InstanceFactory::InstExists:
 	{
-		errorMsg += "An instance with the given directory name already exists.";
+		errorMsg += tr("An instance with the given directory name already exists.");
 		CustomMessageBox::selectable(this, tr("Error"), errorMsg, QMessageBox::Warning)->show();
 		return;
 	}
 
 	case InstanceFactory::CantCreateDir:
 	{
-		errorMsg += "Failed to create the instance directory.";
+		errorMsg += tr("Failed to create the instance directory.");
 		CustomMessageBox::selectable(this, tr("Error"), errorMsg, QMessageBox::Warning)->show();
 		return;
 	}
 
 	default:
 	{
-		errorMsg += QString("Unknown instance loader error %1").arg(error);
+		errorMsg += tr("Unknown instance loader error %1").arg(error);
 		CustomMessageBox::selectable(this, tr("Error"), errorMsg, QMessageBox::Warning)->show();
 		return;
 	}
@@ -828,7 +828,7 @@ void MainWindow::on_actionCopyInstance_triggered()
 	BaseInstance *newInstance = NULL;
 	auto error = loader.copyInstance(newInstance, m_selectedInstance, instDir);
 
-	QString errorMsg = QString("Failed to create instance %1: ").arg(instDirName);
+	QString errorMsg = tr("Failed to create instance %1: ").arg(instDirName);
 	switch (error)
 	{
 	case InstanceFactory::NoCreateError:
@@ -839,21 +839,21 @@ void MainWindow::on_actionCopyInstance_triggered()
 
 	case InstanceFactory::InstExists:
 	{
-		errorMsg += "An instance with the given directory name already exists.";
+		errorMsg += tr("An instance with the given directory name already exists.");
 		CustomMessageBox::selectable(this, tr("Error"), errorMsg, QMessageBox::Warning)->show();
 		break;
 	}
 
 	case InstanceFactory::CantCreateDir:
 	{
-		errorMsg += "Failed to create the instance directory.";
+		errorMsg += tr("Failed to create the instance directory.");
 		CustomMessageBox::selectable(this, tr("Error"), errorMsg, QMessageBox::Warning)->show();
 		break;
 	}
 
 	default:
 	{
-		errorMsg += QString("Unknown instance loader error %1").arg(error);
+		errorMsg += tr("Unknown instance loader error %1").arg(error);
 		CustomMessageBox::selectable(this, tr("Error"), errorMsg, QMessageBox::Warning)->show();
 		break;
 	}
diff --git a/logic/OneSixUpdate.cpp b/logic/OneSixUpdate.cpp
index 65f30cda..cddd0def 100644
--- a/logic/OneSixUpdate.cpp
+++ b/logic/OneSixUpdate.cpp
@@ -96,7 +96,6 @@ void OneSixUpdate::versionFileStart()
 void OneSixUpdate::versionFileFinished()
 {
 	NetActionPtr DlJob = specificVersionDownloadJob->first();
-	OneSixInstance *inst = (OneSixInstance *)m_inst;
 
 	QString version_id = targetVersion->descriptor();
 	QString inst_dir = m_inst->instanceRoot();
@@ -152,7 +151,7 @@ void OneSixUpdate::assetIndexStart()
 	QString assetName = version->assets;
 	QUrl indexUrl = "http://" + URLConstants::AWS_DOWNLOAD_INDEXES + assetName + ".json";
 	QString localPath = assetName + ".json";
-	auto job = new NetJob("Asset index for " + inst->name());
+	auto job = new NetJob(tr("Asset index for %1").arg(inst->name()));
 
 	auto metacache = MMC->metacache();
 	auto entry = metacache->resolveEntry("asset_indexes", localPath);
@@ -198,7 +197,7 @@ void OneSixUpdate::assetIndexFinished()
 	if (dls.size())
 	{
 		setStatus(tr("Getting the assets files from Mojang..."));
-		auto job = new NetJob("Assets for " + inst->name());
+		auto job = new NetJob(tr("Assets for %1").arg(inst->name()));
 		for (auto dl : dls)
 			job->addNetAction(dl);
 		jarlibDownloadJob.reset(job);
@@ -255,7 +254,7 @@ void OneSixUpdate::jarlibStart()
 		QString localPath = version_id + "/" + version_id + ".jar";
 		QString urlstr = "http://" + URLConstants::AWS_DOWNLOAD_VERSIONS + localPath;
 
-		auto job = new NetJob("Libraries for instance " + inst->name());
+		auto job = new NetJob(tr("Libraries for instance %1").arg(inst->name()));
 
 		auto metacache = MMC->metacache();
 		auto entry = metacache->resolveEntry("versions", localPath);
diff --git a/logic/VersionFinal.cpp b/logic/VersionFinal.cpp
index b465df68..ed90c148 100644
--- a/logic/VersionFinal.cpp
+++ b/logic/VersionFinal.cpp
@@ -38,7 +38,7 @@ VersionFinal::VersionFinal(OneSixInstance *instance, QObject *parent)
 	clear();
 }
 
-bool VersionFinal::reload(const bool onlyVanilla, const QStringList &external)
+void VersionFinal::reload(const bool onlyVanilla, const QStringList &external)
 {
 	//FIXME: source of epic failure.
 	beginResetModel();
diff --git a/logic/VersionFinal.h b/logic/VersionFinal.h
index 4ddfe9f4..0bf95707 100644
--- a/logic/VersionFinal.h
+++ b/logic/VersionFinal.h
@@ -38,7 +38,7 @@ public:
 	virtual int columnCount(const QModelIndex &parent) const;
 	virtual Qt::ItemFlags flags(const QModelIndex &index) const;
 
-	bool reload(const bool onlyVanilla = false, const QStringList &external = QStringList());
+	void reload(const bool onlyVanilla = false, const QStringList &external = QStringList());
 	void clear();
 
 	bool canRemove(const int index) const;
diff --git a/logic/auth/YggdrasilTask.cpp b/logic/auth/YggdrasilTask.cpp
index 277d7bfd..7679b11f 100644
--- a/logic/auth/YggdrasilTask.cpp
+++ b/logic/auth/YggdrasilTask.cpp
@@ -54,7 +54,7 @@ void YggdrasilTask::executeTask()
 	counter.setSingleShot(false);
 	counter.start(time_step);
 	progress(0, timeout_max);
-	connect(&timeout_keeper, &QTimer::timeout, this, &YggdrasilTask::abort);
+	connect(&timeout_keeper, &QTimer::timeout, this, &YggdrasilTask::abortByTimeout);
 	connect(&counter, &QTimer::timeout, this, &YggdrasilTask::heartbeat);
 }
 
@@ -76,6 +76,12 @@ void YggdrasilTask::abort()
 	m_netReply->abort();
 }
 
+void YggdrasilTask::abortByTimeout()
+{
+	progress(timeout_max, timeout_max);
+	m_netReply->abort();
+}
+
 void YggdrasilTask::sslErrors(QList<QSslError> errors)
 {
 	int i = 1;
diff --git a/logic/auth/YggdrasilTask.h b/logic/auth/YggdrasilTask.h
index 4a87067a..b24f909f 100644
--- a/logic/auth/YggdrasilTask.h
+++ b/logic/auth/YggdrasilTask.h
@@ -120,7 +120,7 @@ slots:
 public
 slots:
 	virtual void abort() override;
-
+	void abortByTimeout();
 protected:
 	// FIXME: segfault disaster waiting to happen
 	MojangAccount *m_account = nullptr;
diff --git a/logic/lists/InstanceList.cpp b/logic/lists/InstanceList.cpp
index 9a61e2dd..34e6d87b 100644
--- a/logic/lists/InstanceList.cpp
+++ b/logic/lists/InstanceList.cpp
@@ -408,7 +408,7 @@ void InstanceList::loadFTBInstances(QMap<QString, QString> &groupMap,
 			QLOG_INFO() << "Loading existing " << record.name;
 			BaseInstance *instPtr = NULL;
 			auto error = InstanceFactory::get().loadInstance(instPtr, record.instanceDir);
-			if (!instPtr || error != InstanceFactory::NoCreateError)
+			if (!instPtr || error != InstanceFactory::NoLoadError)
 				continue;
 			instPtr->setGroupInitial("FTB");
 			instPtr->setName(record.name);
diff --git a/logic/tasks/Task.cpp b/logic/tasks/Task.cpp
index cb7a5443..c980d6b3 100644
--- a/logic/tasks/Task.cpp
+++ b/logic/tasks/Task.cpp
@@ -22,12 +22,12 @@ Task::Task(QObject *parent) : ProgressProvider(parent)
 
 QString Task::getStatus() const
 {
-	return m_status;
+	return m_statusString;
 }
 
 void Task::setStatus(const QString &new_status)
 {
-	m_status = new_status;
+	m_statusString = new_status;
 	emit status(new_status);
 }
 
diff --git a/logic/tasks/Task.h b/logic/tasks/Task.h
index 80d5e38b..84775407 100644
--- a/logic/tasks/Task.h
+++ b/logic/tasks/Task.h
@@ -58,7 +58,7 @@ slots:
 	void setProgress(int progress);
 
 protected:
-	QString m_status;
+	QString m_statusString;
 	int m_progress = 0;
 	bool m_running = false;
 	bool m_succeeded = false;