Wow. So yesterday I went into Sigil's help files and discovered what the heck "Auto-Tokenise" means -- that, alone, has just changed my whole ebooking life! And even though I don't know exactly what each part of "(.+?)" actually means/does, I do know what the whole shebang together does -- and that, along with "\1", "\2", etc. -- has effectively given me virtually everything that I can imagine I'd ever need to know about Regex.
Omigod! Talk about weird -- just as I'm writing this, an email came in from PayPal notifying me that I just got my refund on RegexMagic! Seriously, talk about a totally odd coincidence. The universe works in mysterious ways...