Not being able to enable imperial ror units in the normal way, I went for an unorthodox workaround; they are now found into the normal recruitment tab instead of the elector counts'.
If I finally got it, I'd modify this, logically.

Fix of the interference with the vanilla imperial knightly rors recruitment in campaign caused by repetition of their same ids, but implementation of modded imperial foot rors recruitment in campaign still missing.

Check–up for patch.

Rebalance Knights of the Black Rose on foot due to their overwhelming overperformance for their cost; 25% more recruitment and upkeep cost, 1 less attack and defence.

Update for performance; low poly file enabled on request for all the foot knight units.

Checked for 5.3 and introduced a newness; the units need stables as second building to be recruited, except for Vampire Foot Knights.