Ok, ta. It seems like 'Wend' is the key command I didn't understand properly, I guess it means wait, rather than 'move towards' as it would have been in Olde English, if I remember right. Anyway...
Why is it a bad idea to run bits of gcode in macros? Not even thought of that being a no-no. Not much at all of my code is in macros; it just seemed to make more sense that bits of code that will get repeated on every file I run should be coded in separately, and called as needed.
Similarly, I didn't realise that calling macros from macros can be problematic. Is it unreliable or something?