Windows GUI编程 - C + SDK或C＃+ Windows窗体

I'm a C programmer with lots of server code experience (AIX, HPUX, some Linux) I need to write a GUI program for Windows (2000, XP, Vista, 7) which requires CAD-like drawing functions and lots of data entry forms (it's a specialised engineering app). I've written some Win32 code many years ago using Gupta SQLwindows (now Centura Builder). The bosses have decreed that it "must be" compiled code. My perception is that C+SDK could do the job but with considerable effort and that C# + Windows Forms would be more capable, but I'm a bit concerned about the .Net framework requirement.I'm a C programmer with lots of server code exp