diff --git a/q3DMASC.cpp b/q3DMASC.cpp
index 0a0a63a..d8ac038 100644
--- a/q3DMASC.cpp
+++ b/q3DMASC.cpp
@@ -133,6 +133,7 @@ void q3DMASCPlugin::doClassifyAction()
 	//now show a dialog where the user will be able to set the cloud roles
 	Classify3DMASCDialog classifDlg(m_app);
 	classifDlg.setCloudRoles(cloudLabels);
+	classifDlg.classifierFileLineEdit->setText(inputFilename);
 	if (!classifDlg.exec())
 	{
 		//process cancelled by the user
diff --git a/q3DMASCClassifier.cpp b/q3DMASCClassifier.cpp
index d46cae2..e6a8ece 100644
--- a/q3DMASCClassifier.cpp
+++ b/q3DMASCClassifier.cpp
@@ -132,12 +132,12 @@ bool Classifier::classify(const Feature::Set& features, ccPointCloud* cloud, QSt
 		}
 		classifSFIdx = cloud->addScalarField(_classificationSF);
 		classificationSF = _classificationSF;
-		cloud->setCurrentDisplayedScalarField(classifSFIdx);
 	}
 	else
 	{
 		classificationSF = cloud->getScalarField(classifSFIdx);
 	}
+	cloud->setCurrentDisplayedScalarField(classifSFIdx);
 	assert(classificationSF);
 	classificationSF->fill(0); //0 = no classification?
 
@@ -552,16 +552,32 @@ bool Classifier::toFile(QString filename, QWidget* parentWidget/*=nullptr*/) con
 bool Classifier::fromFile(QString filename, QWidget* parentWidget/*=nullptr*/)
 {
 	//load the classifier
-	QProgressDialog pDlg(parentWidget);
-	pDlg.setRange(0, 0); //infinite loop
-	pDlg.setLabelText(QObject::tr("Loading classifier"));
-	pDlg.show();
-	QCoreApplication::processEvents();
+	QScopedPointer<QProgressDialog> pDlg;
+	if (parentWidget)
+	{
+		pDlg.reset(new QProgressDialog(parentWidget));
+		pDlg->setRange(0, 0); //infinite loop
+		pDlg->setLabelText(QObject::tr("Loading classifier"));
+		pDlg->show();
+		QCoreApplication::processEvents();
+	}
+	
+	try
+	{
+		m_rtrees = cv::ml::RTrees::load(filename.toStdString());
+	}
+	catch (const cv::Exception& cvex)
+	{
+		ccLog::Warning(cvex.msg.c_str());
+		ccLog::Error("Failed to load file: " + filename);
+		return false;
+	}
 
-	m_rtrees = cv::ml::RTrees::load(filename.toStdString());
-
-	pDlg.close();
-	QCoreApplication::processEvents();
+	if (pDlg)
+	{
+		pDlg->close();
+		QCoreApplication::processEvents();
+	}
 
 	if (!m_rtrees->isTrained())
 	{
diff --git a/q3DMASCTools.cpp b/q3DMASCTools.cpp
index fa315dc..c85c9a5 100644
--- a/q3DMASCTools.cpp
+++ b/q3DMASCTools.cpp
@@ -45,8 +45,9 @@ bool Tools::SaveClassifier(QString filename, const Feature::Set& features, const
 {
 	//first save the classifier data (same base filename but with the ymal extension)
 	QFileInfo fi(filename);
-	QString yamlFilename = fi.completeBaseName() + ".yaml";
-	if (!classifier.toFile(fi.absoluteFilePath() + "/" + yamlFilename, parent))
+	QString yamlFilename = fi.baseName() + ".yaml";
+	QString yamlAbsoluteFilename = fi.absoluteDir().absoluteFilePath(yamlFilename);
+	if (!classifier.toFile(yamlAbsoluteFilename, parent))
 	{
 		ccLog::Error("Failed to save the classifier data");
 		return false;
@@ -109,6 +110,7 @@ bool Tools::LoadClassifierCloudLabels(QString filename, QSet<QString>& labels)
 		}
 		++lineNumber;
 
+		line = line.toUpper();
 		if (line.startsWith("CLOUD:"))
 		{
 			QString command = line.mid(6).trimmed();
@@ -633,12 +635,13 @@ static bool LoadFileCommon(	const QString& filename,
 					return false;
 				}
 				QString yamlFilename = line.mid(11).trimmed();
-				if (!classifier->fromFile(fi.absolutePath() + "/" + yamlFilename, parent))
+				QString yamlAbsoluteFilename = fi.absoluteDir().absoluteFilePath(yamlFilename);
+				if (!classifier->fromFile(yamlAbsoluteFilename, parent))
 				{
-					ccLog::Warning("Failed to load the classifier file from " + yamlFilename);
+					ccLog::Warning("Failed to load the classifier file from " + yamlAbsoluteFilename);
 					return false;
 				}
-				ccLog::Print("[3DMASC] Classifier data loaded from " + yamlFilename);
+				ccLog::Print("[3DMASC] Classifier data loaded from " + yamlAbsoluteFilename);
 			}
 			else if (upperLine.startsWith("CLOUD:")) //clouds
 			{
diff --git a/qClassify3DMASCDialog.cpp b/qClassify3DMASCDialog.cpp
index fc65a8d..90c4f69 100644
--- a/qClassify3DMASCDialog.cpp
+++ b/qClassify3DMASCDialog.cpp
@@ -99,13 +99,6 @@ Classify3DMASCDialog::Classify3DMASCDialog(ccMainAppInterface* app)
 		}
 	}
 
-	cloud1RadioButton->setEnabled(false);
-	cloud2RadioButton->setEnabled(false);
-	cloud3RadioButton->setEnabled(false);
-	cloud1ComboBox->setEnabled(false);
-	cloud2ComboBox->setEnabled(false);
-	cloud3ComboBox->setEnabled(false);
-
 	onCloudChanged(0);
 }
 
@@ -118,28 +111,37 @@ void Classify3DMASCDialog::setCloudRoles(const QSet<QString>& roles)
 		{
 		case 0:
 			cloud1RadioButton->setText(role);
-
-			cloud1RadioButton->setEnabled(true);
-			cloud1ComboBox->setEnabled(false);
-
 			cloud1RadioButton->setChecked(true);
 			break;
 		case 1:
 			cloud2RadioButton->setText(role);
-
-			cloud2RadioButton->setEnabled(true);
-			cloud2ComboBox->setEnabled(false);
 			break;
 		case 2:
 			cloud3RadioButton->setText(role);
-
-			cloud3RadioButton->setEnabled(true);
-			cloud3ComboBox->setEnabled(false);
 			break;
 		default:
 			//this dialog can't handle more than 3 roles!
 			break;
 		}
+		++index;
+	}
+
+	if (index < 1)
+	{
+		cloud1RadioButton->setEnabled(false);
+		cloud1ComboBox->setEnabled(false);
+	}
+	if (index < 2)
+	{
+		cloud2RadioButton->setEnabled(false);
+		cloud2RadioButton->setVisible(false);
+		cloud2ComboBox->setVisible(false);
+	}
+	if (index < 3)
+	{
+		cloud3RadioButton->setEnabled(false);
+		cloud3RadioButton->setVisible(false);
+		cloud3ComboBox->setVisible(false);
 	}
 }