Do I really need to start a new game? Options

[Minarvia]

I read in the Readme that you need to start a new game. I have never installed any version of IA. I guess I need clarification on whether a new game MUST be started, or it is just reccommended in order to have all the extra encounters, etc. I have many saved games for different NPC mods and such and would hate to have to lose them. I intend to return to them later and complete them. But I have no problem in beginning a new game to add to that list as I am trying out Beyond the Law and a few kit mods that look cool. Sooo...new game REALLY needed or do I need to wait to try out IA until sometime in the future?
I hope this isn't a stupid question...