You can use WPILib pre-compiled?
We've been compiling it every time: given the bugs we've found in the WPI code (InArea, FindColor, and GetLargestParticle so far), it is very useful to be able to modify it. What we did was go into windows explorer, and drag-drop every single CPP and H into our project. This ends up moving them all to your project's directory, and then you can freely modify them while still having a backup in c:\windriver\wpilib
Just posted a
thread detailing the bugs we found, in case anyone is interested.