It is the one that always trips me up. I just started in on my third attempt at learning APL/array languages, both previous times I got to the same point where I was mostly at a loss of how to apply it all. So I move on and forget all that I learned until the next time and have to start over. Thankfully the last attempt seems to have mostly stuck as far as keyboard layout goes, makes progress much quicker.

I may take you up on that email offer once I get a bit further along in this current attempt, can't quite form reasonable questions yet and only know what tripped me up in the previous attempts. I believe you are a regular on APL Orchard? I will be joining it soon so perhaps will see you there.