Hello! I'm having the exact same issue. I've tried everything I can think of to get it working, and I've repeated the process countless times today. I'm really at a loss. Only loads vanilla, not even forge.
All the mods show up in the .technic folder, it's all downloaded, yet it's loading Vanilla. Everytime.
I renamed the exact same forge.jar I used to boot it to "modpack.jar," I've also tried downloading a forge-universal.jar (same version) and renaming it "modpack.jar", but to no avail.
It works JUST FINE with curse & ATLauncher. I have no idea what the issue is!