Sorry I haven't cleaned this up yet, and thanks for your question. My intention is to make this more obvious.

GPG, when enabled, completely controls the response to RA error (but not the DEC error). So, RA Proportional Gain, RA Integral Gain and RA Minimum Pulse from that Control Tab are ignored when GPG is used (the DEC values are used, as GPG is not involved in DEC guiding). It turns out the RA Maximum pulse is used for RA and DEC. Maximum pulse is sort of a safeguard that wasn't implemented in the Klenske's GPG code , and so I kept it in place.

The GPG parameters themselves are a bit tricky. I did not modify them from their original form, and you can see how they're used in the code we got from Max Planck Institute / Edgar Klenske:
invent.kde.org/education/kstars/-/blob/m...cess_guider.cpp#L344
Basically it blend the control error:
    line 344:    

control_signal_ = parameters.control_gain_ * input;
where input is the arcsecond guiding error in RA, and control_gain_ is that parameter in the GPG RA Guider Menu you showed
and combines it with a predicted error it's learned from its history
  lines 363-364: