I know this is probably not relivant right now(because 6.0 is coming out right now), but I found a few errors in SPQR 5.0
1. Legionary Cavalry was not recruitable at first. I changed a file (can't remember which one) so all roman factions (not senate) could recruit Legion cavalry after building a big cirucus maximus(don't know real name).
2. Parthia was not able to recruit emortals for same reason
Was this just me, or did anyone else have this problem too.