The PNG files are the compressed image files uploaded with a Sim or lot.
You’ll often find those red/corrupt PNG files when you CUSTARD check a download from the Exchange, but not from MTS or elsewhere.
IIRC, back in 2012, EA had changed some programming involving the Exchange, possibly anti-piracy related. Regardless of the reason, this change caused custom pictures in downloaded S3Ps to read as corrupt in CUSTARD. There isn’t anything wrong with them though.
You can clean the image files out as you have been doing if you like, but you don’t have to. It won’t harm anything either way.
