My reprap pro stopped working well with free tools, and I ended up buying Simplify3D to make it better. That was in 2017 though so I imagine some things may have changed in the software world since then! Sadly I did not have space in my new house for the reprap and it rotted away in a shelterlogic.

Normally I use Cura, but I wanted to try the Cut tool in OrcaSlicer to avoid uploading the whole thing into OnShape just for a couple dovetails. Hooo man, that interface is just... baffling and buggy, actual CAD was the easier approach.