All SVN revisions are buildable, but you need to have the correct compilers (Visual Studio 2008, Visual Studio 2005 and Visual Studio .NET installed, with the project open in Visual Studio 2008), VC Build Hook must be installed, and several system variables must be set to point to the ObjectARX SDK and BRX SDK files. I think Fred has been working on documenting the exact steps to build successfully, so he may be able to add to my reply. In any case, what are your errors?