diff --git a/src/drawdance/libengine/dpengine/draw_context.c b/src/drawdance/libengine/dpengine/draw_context.c
index 3c59ce6d89..30e918152d 100644
--- a/src/drawdance/libengine/dpengine/draw_context.c
+++ b/src/drawdance/libengine/dpengine/draw_context.c
@@ -69,12 +69,14 @@ DP_DrawContext *DP_draw_context_new(void)
     DP_DrawContext *dc = DP_malloc_simd(sizeof(*dc));
     dc->pool_size = 0;
     dc->pool = NULL;
+    DP_warn("Allocate draw context %p", (void *)dc);
     return dc;
 }
 
 void DP_draw_context_free(DP_DrawContext *dc)
 {
     if (dc) {
+        DP_warn("Free draw context %p", (void *)dc);
         DP_free(dc->pool);
         DP_free_simd(dc);
     }
@@ -203,8 +205,12 @@ unsigned char *DP_draw_context_raster_pool_resize(DP_DrawContext *dc,
 {
     DP_ASSERT(dc);
     DP_ASSERT(new_size > dc->pool_size);
-    DP_ASSERT(new_size < DP_DRAW_CONTEXT_RASTER_POOL_MAX_SIZE);
+    DP_ASSERT(new_size <= DP_DRAW_CONTEXT_RASTER_POOL_MAX_SIZE);
     DP_ASSERT(dc->pool);
+    DP_warn("Raster pool resize form %zu to %zu (min %zu/max %zu)",
+            dc->pool_size, new_size,
+            (size_t)DP_DRAW_CONTEXT_RASTER_POOL_MIN_SIZE,
+            (size_t)DP_DRAW_CONTEXT_RASTER_POOL_MAX_SIZE);
     DP_free(dc->pool);
     void *new_raster_pool = DP_malloc(new_size);
     dc->pool = new_raster_pool;
diff --git a/src/drawdance/libengine/dpengine/paint_engine.c b/src/drawdance/libengine/dpengine/paint_engine.c
index 8368d2c170..8089f92f42 100644
--- a/src/drawdance/libengine/dpengine/paint_engine.c
+++ b/src/drawdance/libengine/dpengine/paint_engine.c
@@ -2364,6 +2364,7 @@ void DP_paint_engine_preview_transform(
             DP_canvas_state_height(cs), offset_x, offset_y);
     }
     else {
+        DP_warn("Invalid transform preview dimensions %dx%d", width, height);
         dispose_pixels(user);
         DP_paint_engine_preview_clear(pe, DP_PREVIEW_TRANSFORM);
     }
diff --git a/src/drawdance/libengine/dpengine/preview.c b/src/drawdance/libengine/dpengine/preview.c
index 4dbf3f8acf..3304e75e5a 100644
--- a/src/drawdance/libengine/dpengine/preview.c
+++ b/src/drawdance/libengine/dpengine/preview.c
@@ -304,6 +304,7 @@ static bool preview_transform_prepare_image(DP_PreviewTransform *pvtf,
     pvtf->pixels.dispose = NULL;
 
     if (img) {
+        DP_warn("Transformed on layer %d", pvtf->target_layer_id);
         pvtf->img = img;
         return true;
     }
diff --git a/src/libclient/canvas/canvasmodel.cpp b/src/libclient/canvas/canvasmodel.cpp
index 0a4b1af770..ee28788c22 100644
--- a/src/libclient/canvas/canvasmodel.cpp
+++ b/src/libclient/canvas/canvasmodel.cpp
@@ -356,7 +356,9 @@ void CanvasModel::setSelection(Selection *selection)
 
 QImage CanvasModel::selectionToImage(int layerId) const
 {
+	qInfo("selectionToImage(%d)", layerId);
 	if(m_selection && !m_selection->pasteImage().isNull()) {
+		qInfo("selectionToImage: paste image already exists");
 		return m_selection->transformedPasteImage();
 	}
 
@@ -370,10 +372,13 @@ QImage CanvasModel::selectionToImage(int layerId) const
 		return QImage{};
 	}
 
+	qInfo("selectionToImage: x%d y%d w%d h%d", rect.x(), rect.y(), rect.width(), rect.height());
 	QImage img;
 	if(layerId == 0) {
+		qInfo("selectionToImage: with background to image");
 		img = canvasState.toFlatImage(true, true, &rect);
 	} else if(layerId == -1) {
+		qInfo("selectionToImage: without background to image");
 		img = canvasState.toFlatImage(false, true, &rect);
 	} else {
 		drawdance::LayerContent layerContent = canvasState.searchLayerContent(layerId);
@@ -383,10 +388,12 @@ QImage CanvasModel::selectionToImage(int layerId) const
 			img.fill(0);
 			return img;
 		}
+		qInfo("selectionToImage: layer %d to image", layerId);
 		img = layerContent.toImage(rect);
 	}
 
 	if(m_selection && !m_selection->isAxisAlignedRectangle()) {
+		qInfo("selectionToImage: mask outside pixels");
 		// Mask out pixels outside the selection
 		QPainter mp(&img);
 		mp.setCompositionMode(QPainter::CompositionMode_DestinationIn);
diff --git a/src/libclient/drawdance/global.cpp b/src/libclient/drawdance/global.cpp
index b6992935ab..3a478a71dd 100644
--- a/src/libclient/drawdance/global.cpp
+++ b/src/libclient/drawdance/global.cpp
@@ -131,7 +131,7 @@ DrawContext DrawContextPool::acquireContext()
 	DP_DrawContext *dc;
 	if(m_available.isEmpty()) {
 		dc = DP_draw_context_new();
-		m_contexts.append(dc);
+		// m_contexts.append(dc);
 	} else {
 		dc = m_available.pop();
 	}
@@ -141,8 +141,9 @@ DrawContext DrawContextPool::acquireContext()
 void DrawContextPool::releaseContext(DP_DrawContext *dc)
 {
 	Q_ASSERT(dc);
-	QMutexLocker locker{&m_mutex};
-	m_available.push(dc);
+	// QMutexLocker locker{&m_mutex};
+	// m_available.push(dc);
+	DP_draw_context_free(dc);
 }
 
 DrawContextPoolStatistics DrawContextPool::instanceStatistics()
diff --git a/src/libclient/tools/selection.cpp b/src/libclient/tools/selection.cpp
index 585bd05bf8..607bbabad0 100644
--- a/src/libclient/tools/selection.cpp
+++ b/src/libclient/tools/selection.cpp
@@ -162,9 +162,16 @@ void SelectionTool::startMove()
 
 	// Copy layer content into move preview buffer.
 	int layerId = m_owner.activeLayer();
-	const QImage img = model->selectionToImage(layerId);
-	sel->setMoveImage(img, maskBounds, model->size(), layerId);
+	QImage img = model->selectionToImage(layerId);
+	if(img.isNull()) {
+		qWarning("startMove: selected image is null");
+		return;
+	} else {
+		img = QImage{img.size(), QImage::Format_ARGB32_Premultiplied};
+		img.fill(Qt::red);
+	}
 
+	sel->setMoveImage(img, maskBounds, model->size(), layerId);
 	// The actual canvas pixels aren't touch yet, so we create a temporary sublayer
 	// to erase the selected region.
 	model->paintEngine()->previewCut(layerId, maskBounds, eraseMask);
diff --git a/src/libclient/tools/toolcontroller.cpp b/src/libclient/tools/toolcontroller.cpp
index 3de989dded..c23bbc0f30 100644
--- a/src/libclient/tools/toolcontroller.cpp
+++ b/src/libclient/tools/toolcontroller.cpp
@@ -236,17 +236,20 @@ void ToolController::onSelectionChange(canvas::Selection *sel)
 void ToolController::updateSelectionPreview()
 {
 	if(!m_model) {
+		qInfo("updateSelectionPreview: no model set");
 		return;
 	}
 
 	canvas::PaintEngine *paintEngine = m_model->paintEngine();
 	canvas::Selection *sel = m_model->selection();
 	if(sel && sel->hasPasteImage()) {
+		qInfo("updateSelectionPreview: preview transform");
 		QPoint point = sel->shape().boundingRect().topLeft().toPoint();
 		paintEngine->previewTransform(
 			m_activeLayer, point.x(), point.y(), sel->pasteImage(),
 			sel->destinationQuad(), m_selectInterpolation);
 	} else {
+		qInfo("updateSelectionPreview: clear preview transform");
 		paintEngine->clearTransformPreview();
 	}
 }