I've been monitoring templargfxs-acm-overhaul on mod db for a long time now, peeking once in a while to see what he's up to.
He posted something interessting recently:
1 Nov 2017QuoteA new update will be coming soon with this change included, however after getting reports back from several players on how much this effects the game, I just had to post it now
Inside your games config file (My Document\My Games\Aliens Colonial Marines\PecanGame\Config\PecanEngine.ini) is the following line of code :
ClassRemapping=PecanGame.PecanSeqAct_AttachXenoToTether -> PecanGame.PecanSeqAct_AttachPawnToTeather
Im sure you'll notice the spelling mistake
ClassRemapping=PecanGame.PecanSeqAct_AttachXenoToTether -> PecanGame.PecanSeqAct_AttachPawnToTether
If you fix it to look like the above and then play the game, the difference is pretty crazy!
Why is this line important? There are two reasons :
1) AttachXenoToTether doesn't do anything. Its basically empty or stripped
2) AttachPawnToTether does ALOT. It controls tactical position adjustment, patrolling and target zoning
When a Xeno is spawned, it is attached to a zone tether. This zone tells the Xeno what area is its fighting space and where different exits are. In Combat, a Xeno will be forced to switch to a new tether (such as one behind you) so as to flank, or disperse so they aren't so grouped up etc. (*disclaimer* this is inferred opinion, I cant see the actual code only bits)
Whenever the game tried to do this, nothing happened. Now it does!
This looks like a very cool fix... a possible gamechanger, and an explanation to why the aliens sucked to hard in the game.
A reminder: You can coop and do matches with the mod enabled...
AS LONG AS THE OTHER MEMBERS IN THE PARTY HAVE THE MOD INSTALLED TOO Otherwise you will cause a missmatch.
When the mod is released I suggest we give it go.

V5 is downloadable from Moddb for folk who want to check it out now:
http://www.moddb.com/mods/templargfxs-acm-overhaul/downloads