Despite all the problems, it can be solved by making certain configurations:

What I recommend for stability and performance is to install the beta of the workshop

Then subscribe to Union - patch for Gothic 1, Ninja, Gothic 1 Community Patch and GD3D11

GD3D11 must be configured since because it is 32 bits, it doesn't matter what your PC is, you are going to have performance problems.

This is the best configuration I achieved in the video section (f11) for stability and performance:

1. Set texture detail to low

2. Disable shadows and

3. Activate Vsync

With this configuration I was able to play for an hour without slowdowns or crashes.