I had a problem with launching the game with an AMD HD 5650. Once it would start up, an error box appeared with the message "DirectX Error: Unknown Error," quitting back to desktop.

Fortunately, all I had to do to solve this was to set Runtime.exe game executable to "Windows XP (Service Pack 3)" compatibility mode and it works like a charm.

Hopefully this will solve problems for everyone who gets this issue.

Maybe old graphic drivers. Oddly enough it works in windows 8 without any tampering at all.

I'm on windows 8 but strangely it doesn't seem to work for me...

I'm on windows 8 and the game simply won't work whatever compatibility settings i put I always get this error.