Hiho,
I tried everything, too. The only way I found to get the game started is:
You need the 5x mb alcohol image
and DT4.06
nothing else!
@gundor: you can download again from rapidshare in a few hours imo.
Just mount the image with DT, start the autostart from the mini-image and go on "Spielen" ("Play"), works every time for me. But I can't start it from the Desktop or the guild2.exe ...
Works with every patch (hope with 1.2 too

)
Falls das nicht verständlich war, schreib doch ne PM. Auf Deutsch, gehts besser

wenn's auch so nicht funzt: sehr schade