What does the Event Viewer log show?
I have x64 and play css no problem, I can right click on the boxes and the options are cut, copy, paste and language (uk, us). So the only problem I can think of that might cause it is if there is a problem to do with the languages part of the right click menu which is causing it to crash. It's more than likely because it's not been programmed for handling errors on this and is why it crashes. Do you have multiple languages installed, etc? I'd look at that area first.
Also what is this app you mentioned installing that you need? It might be causing a conflict.