Are your UTAU's frq files generated? EFB-GT usually won't work if they aren't. If they are, re-generating them might help.
There's also a chance that the resampler requires FFTW files to work. I'm pretty sure it doesn't, but I did see one website mention that. It doesn't hurt to download them to your computer if you haven't, since resamplers like tn_fnds definitely need them.
Windows |
MacOS
(I'm not sure how to install these, though I believe the files should be moved to the same folder as the resampler. I'll try it out later and edit this post accordingly. Sorry!)