User conversions and user constants

Unfortunately, I didn't have time to work on YaRPNcalc for quite some time now. I was very busy with my 'real' work and just came back from Frankfurt where we showed our new mixing console for the very first time. If someone's interested in what I'm doing for a living, check out this site: soundcraftdigital.com.
Concerning YaRPNcalc: I implemented user conversions about two weeks ago, but I wanted to add user constants to that before making a new release. I hope I will find the time to do that in the next couple of days.