SIDs and STARs issue for the autopilot to not follow is not the caused by the mod. It’s a bug from the sim for a specific STAR and SID. You fly the same pattern in other aircraft, and the autopilot will bug the same thing, every single time. But any other approach or departure pattern either in the same airport or a different one, is different and may work fine. Even if it’s using the mod or not.
So it has nothing to do with the NX mod, it’s just a bug on the nav and the autopilot for a very specific patterns.