In the latest 1.7.99, there are no solution or project files.
In 1.7.8, you only have solution files (.sln) and no project files, so it fails to load anything...
You are right.
Although the 1.7.99 tarball is not supposed to be used with MS Visual Studio, there is nobody ATM who can do that.
Maybe you could :-)
Try to get SVN source, there are some MSVS files, and you can take a look whether it works or if something has to be done.
CodeBlocks support would be nice, too, I guess that we shouldn't support anything else since it would be too hard to maintain.