An interesting observation I just made a few days ago..
First some background:
All horses have "modifiers" as determined by Native code. They are Lame, Stubborn, Spirited, Heavy and Champion. Each Modifier changes a few stats and appends the name to "Lame", "Spirited", etc.
The same modifier concept applies for all armor, weapons etc.
Regarding the Horses:
I noticed that many of these horses when shown in smaller non-battlefield windows appear different. I was playing another mod from a developer I admire, and I noticed this when I was searching for that companion that was riding a specific spirited "pinto" type horse.. and I could not find it..they all looked like black saddle horses. When I opened up the companions however and searched through one at a time, I could clearly see the correctly colored horse.
I have not tested this.. but it appears that there may be some issue here.
just use the item editor to correct this fault. the second mesh is faulty (cruser, correct is aqs_horse5). is there no testing of the mod?
Are you being serious?
Best,
Saxondragon