Oscam / CCcam advanced functions - prioritizing / ignoring CAIDs

[wikjan]

My CCcam lines are working good for me. Unfortunately there are some satellite channels from Hotbird that are freezing more often than the other although they are from the same package. I investigated the differences between these channels and found that Conditional Access Identifiers (CAIDs) could have influence for that.
I noticed that the best descrambled channels work with only opened Nagra 3 CAID 1803.
SECA CAID 100 gives a bit worst result - 1 or 2 freezes per hour (on average)
The worst thing is with the channels that work simultaneously with four opened CAIDs Viacess 500, Seca 100, Conax 0B01 and Nagra 1803

I have read about assigning priorities / ignoring CAIDs for channels working with many CAIDs and prepared so called prio files.
At first I prepared CCcam.prio file and CCcam.cfg - tried to import it but GTC box noticed only CCcam.cfg to import.
As GTC box converts automatically CCcam lines into OSCAM readers I tried also suitable prio file - oscam.dvbapi . But GTC Oscam import did not see that file.

My question is: How to force GTC DVB Oscam/CCcam to use for example Nagra 1803 and ignore all other CAIDs ?
In other words I’d like to know the real tested way (if exists) to prioritize or ignore CAIDs / Providers in our GTC Android TV box
If somebody knows the way please send me private message (PM)
I hope that there is an effective method to do what I need.
Maybe there is a need to export 5 auto generated Oscam files, edit eg. oscam.server (add suitable lines) and finally import back to box edited files.

[wikjan]

Thank you Eumesmo for your help.
I started with importing prepared Oscam files from USB but finally I found and familiarised Oscam Web interface