New version is out (at usual nexusmods location).
I've tested it and you will absolutely have to start a new career with it, no ifs and or buts. Sorry. I also sincerely doubt anyone's tested it in the campaign mode, so try at your own risk.
Lots of cool new features. Here's a few:
Start in 3025, 3039, 3049 or 3053
Clan Mechs: what's a Clan Invasion without horribly overpowered mechs that'll wipe the floor with you?
Historically Accurate Starmap: Watch in "real time" as the Federated Suns wallop the Capellan Confederation, the formation of the Free Rasalhague Republic. Then watch said Republic get gobbled up by the mechs from the previous item.
Tech Progression: LosTech goes from ultra-rare to relatively common. Uses faction-specific random unit assignment tables (RATs) to determine what you'll be fighting against.
News Updates: Want to know what's going on in the Inner Sphere? ComStar's got you covered for news, Inner Merc has you covered for new tech coming out (first Inner Merc publication out in 3048)
Mission Control included: By default, a few new contract types and randomized spawn locations. If you tweak the config file, you can enable extra allied and hostile lances to spawn as well, as well as make the battlefields larger.
New Flashpoint in 3039
With all those clans and possible extra lances, I might recommend "Bigger Drops".
Lets you drop up to eight mechs, given a significant investment in the argo upgrades it adds.
There are also a couple of extra flashpoint mods that should be compatible:
"It Came from the Rim", "Jinxed" and "The Periphery is a Harsh Mistress", that'll get you four extra flashpoints.
I'd like to play "The Cache", but there's a bug in it that gives you like a hundred mechs once you complete it, leaving the rest of the game kind of not a challenge.