oleg7, I have not tested this feature but yes you can load soundfonts or soundfont wavetables. I believe the accompaniment cannot use these soundfonts but your left hand and right hand keyboard voices can. I have used version 4.0 for a while and am currently testing version 5.0.
I guess from my perspective, I would prefer a style player which focuses primarily on the accompaniment and less on these esoteric features. With forte Ensemble or other hosts and software synths these features become superfluous. Some of the other arranger/workstation type features may be interesting, e.g., harmonies, play mp3 or midi clips, etc.
I would even take a good XG to GM conversion over some of these features.