As Malleable above, I use the FULL ruleset (RMSS/RMFRP) with custom rules from RM2, RMC, Guild Companion web, other publications, own creations, etc etc.
The main feature needed for any software relating to Rolemaster is, as I am always stating, FULL costomizability.
Software supports attacks? Cool. Let me add weapons. Software support spell casting? Cool. Let me add spell lists. Software supports Chargen? Cool. Let me add races, professions, training packages, and skills. Software supports equipment, inventory, and treasure? Cool. Let me edit everything.
So far there is already a large collection of threads on this forum covering ERA. I tried searching them for info on what is customizable and how. When I find out, I may buy ERA. For now, I'm kind of on the fence. I bought Combat Minion licenses (both of them), All books ever published in softcover form, every available pdf in the old ICE store, most pdfs from rpgnow (those that were updated), and finally RMC for Fantasy Grounds. I'm fine with all that of course. However, none of the software products completely covers my needs, all of them for the same reason; lack of customizability.
My question, therefore, is this: Will ERA let me add races, cultures, training packages, professions, weapons, skills, spell lists, and whatever else I need?