I hope this is okay to ask here but, I am engaged in a side project to create an AOS OSI replica back before the map changes. Is there a way to rollback your client to 4.0.1b or is there a place I can get a hold of the Age Of Shadows client? I lost my disc.

Seems like the right place to ask

I don't know of any way to roll back. But you can install an older client like Second Age or UO:R and than patch up to 4.0.1b. With the task manager open you can "kill" the patcher as soon as it reached 4.0.1b.

Google UOAOS_July_03.exe and download it, that's the AOS installation. IIRC the client starts out at 4.0.11c.

From T2A to gold_win32_4-0-1b is only 21.2MB of patches.