ApexSQL Mask - Single column Mask generating 1+ GB script??


I am a new user to ApexSQL Mask and trying to do a simple masking project for an on-prem database. I am starting with a simple substitution and trying to mask a single column with a pre-defined mask value as a quick proof of concept. I have deselected all other columns and tables from my database, but for some reason everytime I generate a mask script it generates a 1+ GB file with updates to tables I don't have selected for masking. I have nearly 100 tables in my database and I have gone through all of them 1 by 1 to assure I dont have anything selected to mask yet the software appears to ignore that.

Anyone else encounter this? This is extremely frustrating given I just purchased the software for an immediate need and it appears I am better off masking manually.