This didn't quite work for me and I'm try ping to work out why. The Liverpool group was v good, and I guess you started from there as it's got 2 red herrings for the other groups. Trouble was I think that the solver can quickly brute- force two of the other groups without working out their precise connection- and the precise connection was a lot tougher than finding the group. (For a southerner.)

I thought the grid was ok. I didn't get the point for regnal names nut I gave it to myself any way:-)

Canal group threw me, otherwise not too tricky. Fun though.

Mindnumbingly easy. Finished in 20 seconds. yawnarama city!

btw ignore Mister Tom - his grids are worse than yours. Other than being too easy this grid was acceptable.