Sometimes it's necessary to fix something but you don't want to open it up in CTU or TSRW (or it can't be opened), this is basically what the CASP file is, it holds the information on gender, age, file names, categories etc. Please note that this can only be used for CAS content, I found this while investigating Peggy files, I don't know if anyone has ever found this out or not but I haven't seen it being used before so at the very least it may bring the method into better light.
What this will teach you
How to fix a CAS parts age, gender, categories etc. in S3PE
How to make things unique (not overwriting anything) in S3PE
What this will not teach you
The basics of S3PE
Where to download S3PE
How to install .packages
How to make apple pie
Okay first off open S3PE and the .package file you want to edit. Look for the CASP file in the tags column.
Then look down to the bottom and click on "Grid" this screen should pop-up
It should be pretty self explanatory, the 3rd one down you can see the file name which is what makes it unique. Then you see AgeGender and ClothingCategory the two you should be focused on.
Here is what the AgeGender looks like. Just change from true to false (or false to true) to make you edits! Easy right? Just click commit then save! You're done! Congrats!!
Note: Make sure S3PE is completely up to date, I've been told that having an older version doesn't allow you to use grid.