Possible idea how it happens. I was haveing a great old time
placing down a road way , then once and awhile i would mistype location like 6340..21 instead of 6340.21, I would get a error message, but i could continue . everything was fine, made my PBO loaded in OFP and tested the island. every thing went well.
However if i try to reopen that wrp file. I get the same error you are getting .
Bummer too, because i was almost finished with the roadways
40 plus hrs placing down sections :'(
Hopefully this rabeling will help as a clue to find the problem to fix your file.
For others just starting with wrpedit, save multiple wrp files, so if this happens, you dont have to start from Scratch.also if you do get a error when placeing a object because of a mistype. exit wrpedit, and startup one of your last saves.
PS is there a place we can post our islands for others to test or enjoy ?