I ran it on the .Net Server Enterprise Beta (now Server 2003) since October or so, and I didn't have any trouble. (Beta's dead, sigh. I ran and wrote scripts on it, and also ran and wrote scripts on XP/2K/NT/95/98 at the same time. I didn't find any interoperability problems with any of these that were the fault of the OSs.
So, I'd have no problem writing ST scripts using, say, NT or 2K, that I expected to run on Server'03.
I've found that a dialogs system controls, i.e. Minimize, Maximize, Restore are not recognized. Minimized windows are not seen. I use a RestoreWindow api to get around that. Other than that, all scripts run fine.