If exporting to png isn't working, then indeed it looks like a GDI+ error.
1)Can you copy the newest gdiplus.dll in your development machine to the folder where you deploy the console app so it uses that one instead?
2)If 1) fixes the error (let's hope so) can you try maybe to install this update in the servers?:
I've tried it here with WS2008 R2, and from what I see in that page, this hotfix applies to WS2008 but no WS2008 R2, maybe it is related.