Add some null reference checking to the GDI rendering in the preview. For some reason, my window was displaying as a 0x0 window, so it couldn't get a visible graphics object to operate on, and would crash without me being able to fix it up.
3.0.8r2 changes (trivial).
Merge pull request #48 from sall/master

Merge from sall/vixen
Merge branch 'master' into VersionControl