Thanks for letting me know, I’ll take a look at why this might be happening. It seems to be an inconsistent issue, since it works most of the time, but sometimes fails. You can activate the masking again by selecting another item from the Supernatural category. While this is not a fix, it’s a workaround you can use on your characters if needed in the meantime this gets properly patched.
I’ll also check why larger size images aren’t allowed when uploading.