Double entries are likely cause by your having the same rom with different filenames in the same directory.
Tutankham works fine here with 32K (I also have a nanoPEB).
I went through several of the WHTech roms today/tonight and while I was going to report several not working, they just seems a tad finicky, and after running a couple "cartridges", resetting a couple times, then going back to a non-working cart, it would suddenly (and repeatedly) start to work.
Of all the ones I have installed so far the only one that simply refuses to load is Card Sharp.
Gotta say though, having access to RXB and XB was wonderful. That and being able to run a couple programs I've never seen on a real 4A (The Ludwig Von Drake Disney Education Game, Verb Viper and Germ Patrol immediately come to mind) has made my first FG99 week-end very enjoyable.
Full disclosure, I did pause to watch the new King Arthur movie but wish I would have just kept fiddling with my TI (two hours of my life I'll never get back! ATTN: Guy Ritchie, stay away from period fantasy epics - you suck at them!) Looked pretty though,.