The Make VS.NET action parses the solution/project file to determine the correct version of devenv/msbuild/vcbuild to invoke. You can override this via the 'Override...' field on the Options tab:
http://www.visualbuild.com/Manual/vsnetoptionstab.htm
But please ZIP and post or send:
1) The info from Help | About | Install Info
2) The .bld file used to build
3) A build log file
4) The .sln file and project files being built (no source code files)
as that shouldn't be necessary.