From Rockford Lhotka's Expert C# 2008 and VB 2008 Business Objects books
What's the difference between the cslacs.sln and the csla-build.sln solutions?
cslacs.sln is the solution you should use.
csla-build.sln was used for a (now defunct) build server, and really only worked if you could emulate the exact configuration of that server environment.
Rocky