R.R. Bowker's Software Encyclopaedia 1992 also lists Dynacomp selling versions for the Apple II and IBM PC clones.
Jason Dyer has covered the game as part of his All the Adventures project.
[+] Users who have solved this game
[+] Users currently playing this game
Sorry to point it out but Wembley Castle was never released by Dynacomp. It was a North Star release.
Whembly even.
This thing is enormous. I have currently mapped 319 rooms and I am still going. I think the mazes herein may be a larger ratio of the game than even Acheton.