[DUG] SQL Issues

[Marshland Engineering]

I have got to the end of my tether. Table not in insert mode. I have quite a
few programs that use single tables in forms with editing and all is well. 

This new form has editing in 2 tables and here is where the trouble starts. 
Even if I don't enter any data and just close the form, I get not in edit
mode. I've take off all the SQL relationships to try and find the issue but I
can't pinpoint where it lies. If I leave the tables in edit mode, all is ok if
I post and them immediately put them back into edit mode, I get a crash.  

Is there anyone in ChCh who is willing to spare a hour or 2 to give me a hand.
Help with how to debug something like this would be very handy.

Cheers Wallace 3237449