Thanks for sharing. Yeah, I have been meaning to go over to the Wishlist forum and post a request for more sanity checks. Although DT Register has a lot of flexibility, it is really, really light on informing you that you've broken something and the software isn't going to work.
A good example is the email sanity check he put into place where the Email tab highlights in red if you haven't filled that info out yet. Had that red tab not been showing up, you'd be wondering why things aren't working.
That Admin mail field stuff mentioned earlier in this thread would be another good one. Maybe there should be a "Sanity Check" tab added that can tell you the various status states of important fields (ON/OFF, empty/unconfigured). There are getting to be too many things you need to tweak in different places and its easy to lose track of them all...