Problem : after installing McPhat liveries (25 from WA1 to WA5) I noticed that you absolutely CANNOT edit your aircraft CFG file or when doing so FSX will not be able to "read" this file and show the liveries properly next time. I asked McPhat about this, probably some kind of security/protection issue for them ? Anyway very frustrating as I always edit my aircrafts CFG file to change UI_typerole from whatever is shown to the aircraft in question. (from "Commercial Airliner" to 757-200 in those cases)

SOLUTION : after you edited your CFG file with McPhat liveries, you have to repair CS757 base install so it writes another clean CFG file (CS 35 liveries) and then you can't copy paste from let's say you did a backup from the CFG file with McPhat entries, as it would corrupt the CFG file. YOU HAVE TO ENTER ALL THE LIVERIES ENTRIES MANUALLY in CFG file. Look at your CFG file with McPhat entries, open a second windows for your repaired CFG file, create new Aircrafts XX block (25 of them) and copy one block by one block what xou find in your other CFG file. DO NOT USE McPhat INSTALLER if you need to edit your Aircraft CFG file for whatever reason, it will corrupt your file and screw your install. Hope this helps