[PlasmaKrab]

First thing, the picklist folder has no relation with images. It is about telling the IA what to buy.
LBM pictures are in the Game Data\Pictures folder, and you can add pictures with any free number that is not used.
LBM files are named "PMxxxxx.lbm", 'xxxxx' being any number between 00000 and 65535.
Check which numbers are used using MOBhack or looking up the folder.
I don't know of a complete LBM list available anywhere, there are several thousands already. I have started referencing some of them for my own use, but I am in no way able to ID every single picture.