Yes, quite enjoyable.
5a - shame on you. It jumped out at me as I was printing.
My last ones were 1a & 1h, crucial lights, but the crosses at the Z & Q gave a good start.
Thanks syzygy, very enjoyable with some clever economical construction...Ring 2 got me started, hadn't heard of R1h before, it seems to rely on an abbreviation I haven't come across...from US sport maybe?