Been experimenting with launching demos.
From the first page there are a few that either hang or quit to a grey screen on my setup (3Ddemo2, 9Fingers, Bacteria an also StateOfTheArt as mentined earlier). However these demos also have issues when loaded by clicking on the icon from WB so it's not TL's fault! For example, from an icon double click launch, StateOfTheArt F10 quits to an Exception "Access Fault" error. SO I guess this type of error causes TL to hang on a grey screen.