Hi rjlee,
thanks for your thoughts - they help me making my mind up.
Yes, Visual is not the platform to generate the whole thing on from the scratch, you are right.
I reckon to build the framework on KDevelop/gcc and keep an eye on portability to Visual C++.
There is a project I admire very much - the dcmtk (
http://dicom.offis.de), that gives you an industry strength DICOM messaging library on BSD license, and this is cross platform "like hell" - it impressed me. But, they did it the hard way, not using STL at all, all "elaborate" functions hand-knitted (strings, lists etc.) but it was started years ago.
In my Visual C++ .NET (2003) there is a fairly well implemented support of STL (announced as a "new feature"

), and that made me think of using it.
Loads of projects are using the proprietary Visual C++ with MFC, and I would like "my" framework to smoothly integrate there too - so you can add GUIs with MFC as well as QT or KDE or GTK or ... or... - See, its a matter of freedom of choice.
No Microsoft Support will exclude the still popular Windows platforms - yes, I know the QT (expensive for MS-Windows) and GTK stuff, but - for the GUI Part, this is not "it", if you know what I mean.
Thank you loads!
G'night, Peter