Defoko's bank (uta in the voice folder) is configured and encoded in Hiragana and is CV format. This bank will only work with single character input as the lyrics:
ex. [か] [え] [る] [の] [う] [た] [が]
Teto's voicebank format (and therefore the lyric input) is dependent on the version you download. It comes in CV, VCV, and CVVC Delta English as well as appends. Each append has a different suffix associated with it.
Teto's CV input is the same as Defoko's.
The VCV format requires the following format for lyric input...
ex. [- か] [a え] [e る] [u の] [o う] [u た] [a が]
CVVC Delta requires familiarity with the X-SAMPA format. I'd provide an example, but I'm not well versed in this format. For append versions, you'll have to Ctrl+G to open up the voice configuration window and see which suffix is used.
The default resampler and wavtool should work for both of these voicebanks, but running UTAU as admin or changing your permissions so that User has full control and turning off the Read-Only permission for the parent folder (C:/Program Files (x86)/UTAU) should rectify any problems with rendering or producing frq files.