Files do not appear on Sansa Fuze+

I have just downloaded 4 talking books to the Podcast section of my Sansa Fuze+’ hard drive, but only two of them appear on the unit’s screen, even though my PC shows all 4 are there. It’s happened before and I think it’s something to do with the ID3 tags - which is where I get a big problem. I’ve tried using the recommended bits of software (Tag & Rename, Media Monkey, MP3tag, ID3tag Editor etc) but I’m afraid I just get my head round any of them. Is there a straightforward bit of software that automatically makes any MP3 file suitable for playing on my unit with just one click, or should I try and find a less fussy player?