We started to fix the Windows build. Bug reports and patches are coming soon.
Excellent initiative Ossy! And nice division into sub-tasks for the individual issues. CC'ing Joel who is also looking into the Windows build.
Closing this bug as resolved. Trunk builds now with Qt5 and MSCV and we have a bot. There are many more things to tweak, but I think we can take them in individual patches that don't require special tracking. Such as MingW support.