the reason is quite simple and easy to fix it seems you have added in custom ridables, i released about 15 to 19 new mounts for the SA-project but they work in a few other versions too like svn+Ml 526 you will need to be patched to atleast 7.0.8.1 and need to add in my tiledata that comes with the download.
It seems as if you may not be fammiliar with the tiledata.mul file in your Uo directory, if this is the case then you would most deffinetley not have a modified file. Therefor downloading my release would not cause any clashes.
If you choose to use the version i released which will give you alot of mounts to play with instantly, then go
HERE, it is a simple download and just throw the mounts in you customs scripts then add the tiledata to your Ultima Online folder making sure to back-up the original or move the original to desktop then replace the new one in the Uo directory.
Restart server and run razor not CUO test the mounts out should be all good and visible. Then make your patches and upload them so your players can see them.
Or....
You could just modify your tiledata to suit the mounts you have but i dare say if you just got the mounts of these forums and tried to make them work, it is exactly what i did and got them visible so it would probably end up being the same mounts.
*NOTE i did make a couple of custom ones in this package and am due to release more soon. (plug&play)
