Hi guys! Busily working on Phatty OS 3.0 as we speak. This will be a major update in terms of stability and ease of upgrading... finally the LP (and Slim) gets a permanent boot-loader, so it will always be able to recover and try again in case of any errors during firmware update.
OS 3.0 will be unified across all Phatty synths, so they will all get the same basic features including the new tuning scales option.
A scale editor for Mac and PC is in the works, so users will be able to define their own custom scales and tunings. Right now this is limited to defining 12 custom intervals and setting the root note, so you can't do anything really esoteric like 19-TET or Harry Partch tunings, but you can do a lot of the alternative scales people use more commonly (pythagorean and meantone type scales, anything based on 12 tones/octave).
It will take a little longer to roll out OS 3.0 for existing LP users, because it's easy to build the new Slim with bootloader already installed but more difficult to create an update process that cleanly updates an existing unit. We are working on this update process now, but we'll want to test it carefully before releasing to the public. Stay tuned, though... good things are on the way.