From first post:
"can be omitted for a first try; if B (castle), C (city), T (temple) or U ("uncivilized" = tribal) is in put in brackets after the names those baronies will be built at game start."
Well, I was trying everything I could think of short of writing a python script to edit the provinces files after the fact, and I put brackets on everything I didn't want to build in provinceDef.xls. The brackets did the opposite of intended-they were commented out, but the brackets also showed up in localization.
I figure this is not intended anyway, but I was just trying out solutions.
If you put a "(B)" there you will get a castle. If you don't it won't be built unless you write a holding number with an underscore there. If you just put "6" there will be 6 holdings, one built. If you write "3_6" the top three holdings will be set as built. The order is Castle, City, Temple.
What is your problem there? If you don't want any additional baronies built, fine, just write 1_6 or just 6.