Acad2004 & Odcl 5.0.1.1
Have VisualLisp window up and AutoCAD window up tilled vertically. Docked form with tree in AutoCAD. Click on node in tree. Then click on Visual lisp window. An outline of a window appears on the display located at the cursor pick point similar in shape to the docked form. Minimize then maximize VisualLisp and problem cleared.
Jim