While browsing around YouTube a while ago, I happened across some video tutorials. They are for RMVX only, but it shouldn't be difficult to port them over to RMXP. I've actually been going through them recently and have been learning a few tricks.
The first video tutorial - "vidorial"? - addresses a commonly asked question: How to remove the Save option from the Status Menu. Simple enough to do, but there are other areas you'll need to find to completely disable it, as the video explains.
Anyway, enough preamble.
Most of the tutorials on this channel are quite informative, easy to follow, and aimed more at the beginner to intermediate programmer. I'd highly recommend viewing the videos from the beginning. Experts, however, obviously have no need. At the time of writing this post, the current tutorial is at 18.