After creating text, I find that other drawing tools do not function. This occurs immediately after an area for text has been created on the document (i.e. when the vector layer is created). Deletion of vector layer does not resolve the problem. 
The document can be saved and will load and function normally until another text layer is created.
I have seen in earlier versions that text appears "hairy" when editing - certain fonts (like Levi as used by David Revoy in a tutorial) but not when the area is released to work with other layers.