OK, here is a link to Vsig 2.8.  This is the last version we built from the original Vsig codebase, which can read sig files in the original format as well as writing sig2 files.

    Vsig 2.8 (Windows) : https://etide.io/Qlb6F

It doesn't support the MIDI communication protocol, so you'll have to use the sig database containing the H7600 modules information:

    H7600 Sig Database: https://www.eventideaudio.com/support/downloads/h7600-vsig-database

We've tried this with a simple sigfile and it worked fine, but we don't know how complex your sigfiles are or what modules they contain so results may vary.  Please let us know how you get on.