Haven't been around in the battlefront modding community for many years now, but a couple of days ago curiosity hit me and I downloaded the ModTools again.
I started writing a Library in C# for reading various File Formats like MSH. Ok, up to now just MSH is somewhat implemented

I uploaded it on GITHUB, so if anyone is interested in contributing you're welcome

In parallel I also did a GUI Editor for MSH Files (You can find the binarys HERE)