I have tried to implement cutter compensation for a while but never had any luck.

Whatever I do I always get some errors in Mach3.

I made a short recording that goes trough programming a part and importing it into Mach3. I would appreaciate any tips and suggestions.

https://youtu.be/3ZeYL-pW3V8

I attached the g-code and the fusion archive file.

Mach3 needs a lead in and lead out with a line and radius the rad must be tool rad plus a bit and line length has to be tool rad plus a bit so if using a 10mm dia end mill lead in line could be 6mm and rad 6mm then all should be good.