You can always PM me. I myself also have a batch of recycled PA2200 bought from another 3D printing service. Shapeways wouldn't sell me at the time.
Sintering PA is extremely hard and focus lacks vital hardware. The things it lack are:-Heated buildbox or external layer heater, -Oxygen free (Nitrogen) environment, -CO2 laser capabilities.
You need to heat the powder to just below melting point before you can start laser sintering. this is a problem for Focus since MDF does not handle heat that well. The oxygen free nitrogen environment could be made to encase Focus completely, but you do need it to stably print for long times. CO2 is an absolute must, Nylon can't really be sintered by any other laser, simply because it is too bright for all other wavelengths.
Focus has failed to prove itself for SLS printing, but has more than proven itself in 3DP (Zcorp) printing. I am currently working on a new printer that has a much better powder handling system made from aluminum. It can be used with CO2 safely and can be heated if necessary. The gas environment is not needed for me, so you'll have to solve that one on your own.
Sadly, my own SLS project have been postponed until further notice, due to complexity and other techniques that are cheaper and simpler to build (expect a dedicated 3DP printer in the next 6 months)