mmmmm...yes I did all this already. :confused:

I have Unofficial Oblivion Patch
and I said in my post I did toggle both rider and horse to not corpse check.

Well...I guess I will check to be sure Unofficial Oblivion Patch is launching in my OBMM.
If I tuned it off by mistake that would explain why all the sudden I am seeing this issue.

edit: no, I do have the Unofficial Oblivion Patch ruining.

I solved some of my issues by making the horse and the NPC do high processing until they are ambushed by the player.
But they still stop dead and trot over to any dead body they pass by.
Then take off fast again after walking over the body. Its like she is stopping to loot them or someting....

WEIRD!

Ok, Arthmoor. I just finished 4 tests of gauging the NRB guard's reaction when initiating combat with him.

In three of the tests he runs over to me and does the STOP, CRIMINAL SCUM thing while still mounted. A couple of times he did have trouble turning around on the road beside the Inn before he darted right at me (even when I was in 100% sneak mode). When I "resist arrest" he just walks away on his horse (no greeting like AndalayBay gets), but when I ref him his current AI package is Combat, so he's searching for me. He just wanders around beside and in front of the Inn. I can walk right up to him and he just wanders with that goofy grin on his face. A minute or two later the legionnaires will kick into combat AI too and come after me. (wth is combat AI?)

The fourth run he actually did get off his horse before reading me my rights, and when I resist things fall out as normal and combat is engaged. I'm thinking it's a can't dismount issue?

My abomb is only at 2%. I'm still doubtful that'll help but I'll try clearing that next.

When I get a "greeting" it's just a passing greeting. He doesn't enter dialogue with me. If I enter dialogue with him, then he will try to arrest me.

Damn! (Sorry for the threadnecro BTW). It seems I have become a victim of this TCL-curse too! Guards and highwaymen do not stop me anymore (no forced greeting). Starting a new game reveals that this is an issue affecting only my current savegame character, not a mod related one. It seems as if the NPCs can't "reach me". Testing this with a new character did not reveal any such issues. There have been a couple of rare instances where my character has "got stuck" on the ground also (running a few inches above the ground). I have tested this with several load order options (disabling guard overhauls and such) but this clearly a savegame related issue and I bet TCL or somekind of animation thing is the culprit. However I see little hope of fixing this. If anyone has succeeded overcoming this demonous bug please let me know. PPLLLLLZZZ!1

Just a thought -- Are the path grids in the area hand placed ? -- might try raising them just a bit and see if that helps any -- could be they are placed just a bit below the surface causing the horse to drop down and then getting stuck down there.

^It seems that my problem is a global one and might not be related to the OP's problem, and my intention is not to hijack his thread. It just seems that this might be related to a bigger yet undiscovered glitch in the game caused by the abuse of the TCL command. I'll try to disable OSR and see if that helps.
EDIT: well, it wasn't OSR which was expected. One of the annoying things is that while one horseback the player character freezes when the highwaymen try to initiate conversation. Only way to get out of this situation is to kill the highwayman via console. I'm gonna try the stat cleaner, but I doubt it will help either. I think this might one of those fatal game breaking bugs. I'm gonna go through my savegames too, that might help me close out some suspected culprits.

Just to clarify: for me it had nothing to do with TCL since I rarely use it. For me it was having that version of Faregyl loaded, which is what Arthmoor was asking about in this thread. I haven't tried the release version of Faregyl.

ok, it was just that Mahjers mentioned a similar problem in the beginning of the thread and the symptoms appeared to be similar. I guess I'll have to do more digging to find out if anyone else has come across this strange glitch.