The GUI bindings are usually the hard part.
Do these not work? (Not a rhetorical question - I haven’t tried them.)
The project also seems dead since 2020 or so, a current fork is https://github.com/bluszcz/cutego/ But I haven't tried that one.
If you just want to pretend modules never happened, then export GO111MODULE=off and use the latest Go compiler.
In general, golang seems to work best with golang-only projects. As soon as there are other languages in the mix, like C++ here, things get very ugly very fast.