Well I decided that knoda isn't what I need for forms design etc., it's simply not powerful enough, no calulated fields in forms, no triggers, etc.
So I was getting a bit despondent really but decided to look and see if the postgresSql site had any useful links, I;m not stuck on mysql, postgresql is just as possible.
Well, after a few blind alleys, I came across Rekall and, so far, it looks as if it's just what I want. It works with mysql as well as with other databases so no problems there. It's a KDE application but I just downloaded the source tarball, did a .configure and make and the thing built flawlessly. It took a *long* time though, it's a big application.
It seems to have the forms capability that I want. It has macros (rather like access) but also has more (for me) understandable scripts written in python.
I'm just exploring at thehme moment but I think I have what I want.
It's remarkably well hidden for such a comprehensive application.