Yeah, it's a big mess (in a good way).
Honestly I've been waiting to see if things would settle down.
The big development is that the author of Xnp2 (a fork of np2 for Linux) has been improving the i386 core. Xnp2 is open source, so everyone is adopting his code.
The author of the kai builds appeared again and started adding features again, mostly more disk formats and some features already present in np2fmgen.
Warning: the code has been tweaking the floppy drive system so there may be some bugs which could corrupt files. Always keep a backup of your disk images.
np2_085kCVC8 - for PC-9801
http://www.mediafire.com/?8ocxm18v698b4c6np21_083kCVC8 - for PC-9821. 0.83 code base.
http://www.mediafire.com/?2m88p1prpg1px84np21_085kCVC8 - for PC-9821. 0.85 code base. 0.83 and 0.85 are identical except for the i386 core. Performance is better with 0.85, but 0.85 crashes with EMM386.EXE and you'll need to use an alternative memory driver like VEM486.
http://www.mediafire.com/?ry6su3n8nac39s5np2ss3a - Another build, using VC6 instead of VC8. Also has multithreading. This is more of a test version.
http://www.mediafire.com/?t63sikgag5n2jkxThe fmgen coder also adopted the Xnp2 core, which broke stuff initially but I think it's mostly fixed now. He's also been working on PCM audio recently. The latest version makes an XMS fix to the 286 core, but this may cause other problems.
np2 fmgen 2012-02-07 - without the 286 fix
http://www.mediafire.com/?zz7w88lzh89zmnfnp2 fmgen 2012-02-13 - with 286 fix
http://www.mediafire.com/?s4e38p8ez7v9txcfmgen dll set (v1) - external FM synth engines for use with np2 fmgen. Add "FMGenDll=xxx.dll" to the .ini file.
http://www.mediafire.com/?cja10ogt54tp2j2For general use np2fmgen is still the best overall and it's got a lot of good features.
If you have a slow computer or just want to crank up the clockspeed for the 3 games that actually need it, try the kai builds.
edit: First post updated with new information.
edit2: I wasn't reading closely enough, the kai author and the ss author are in fact different people.