It looks like this version works well in Sfizz (and on Zynthian). I tested it and it worked fine. You can keyswitch between Natural and Retuned. Also release time with cc72 works so thats quite handy. Even the Flac samples work on my Zynth.
This one is based on the Salamander and offers 4 different timbres. They work nicely on Zynth!