manjoe
Sorry to butt in and I know this will sound preachy, but your use of the term KUID in this case could be 'dangerously' misleading for those less experienced.
People refer loosely to KUIDs as the actual objects, but in reality KUID is the unique identity number for an object and you don't mess around with it. Even if you did, it would not change the region in Surveyor.
In TRS2004, the config tags to change are region and maybe also category-region-0. In TRS2006, I think they abolished region but still use something like category-region and that's what you change, as edion2 described.
We are lucky with TRS2004 in that we can alter the region of hundreds of objects at once using Trainzobjectz. With TRS2006, it sounds like the poor punters still have to edit objects one at a time with CMP.