Sorry Henning, stupid mistake to make, corrected now. 
I think your library contains a bug, printNumF doesn't display numbers correctly if they are less then 1 (0.1, 0.2 etc).
I got around that by simply adding '0.' in front, maybe something you can look at.
Otherwise it works brilliant, maybe a bit slow but I'm not sure what the limiting factor is. I try to keep refreshing things to absolute minimum 