Hi Piers, Yes, welcome. Forgive me for sounding harsh. but asking about a version that is effectively completed unsuppported in practice and on the list is roughly the same as asking for support for WIndows ME now on a WIndows 10 list. Not sure where you even get 2.16 from now!
Also, in my hurry to point out the Notation Reference (which here we refer to as the NR) I didn't check your code in 2.21. My bad! Part of the reason I didn't even compile your code is the ancient version. Please, do upgrade. Andrew
