Steps to recreate:
1. create a new sprite object;
2. close animation window;
3. click "edit" on the animation, under the properties bar.
Then C2 goes white and Windows 7 says C2 crashed.
I'm using C2 r99 x64 on Windows 7. All my drivers are up to date.
Also, this happens whether you have something drawn on the sprite or not.
EDIT: Forgot to say, this does NOT happen if I double click the sprite, or right-click and select "edit animation". It only happens when you go to the properties tab and click on "edit".