I can not find any other Sysara related documents on the WWW
I looked using the other name you gave (i.e. Arasys), and found lots of stuff, but most of it just for weight loss etc. They refer to its initial design for ms, but that's about it. As you said it "failed" for ms. The one interesting reference I found was at http://www.lemuriaspa.com/arasys-the-science.htm
which wrongly referred to MS as a "muscle wasting" disease.
The co-inventor of the pacemaker, Gerry Pollock originally designed this system to help muscle-wasting conditions such as Multiple Sclerosis and muscle atrophy.
This would become interesting if it did work on muscles, and they found the "frequency" that caused nerve regeneration.