.sng files are set up for Edit Track II and Yamaha PSS-790
.mid files are midi1 files for any sequencer.
These are songs that I did two years ago on my Juno 106 and Casio CZ 101.
About a year ago I bought a Yamaha EMR-1 from Le Sysop.  Many of my songs
were keyed with setting off patterns on the EMR instead of individual drum
patterns.  After I got the Yamaha PSS-790..I converted the patches over
but left the EMR settings and did not upload the songs to C.C.B.B.S. 
Recently I experimented with putting PSS-790 drum tracks into "Whiter
Shade of Pale" and it worked easily....so I started to convert some other
songs that I did over the last two years....enjoy...YODA