Not sure what I just done but its working 
using 1200 CPU
I started everything again from scratch, new device, new project and it now works.
I cant see it in the manual but I had to set the tag to have the “DB” part in capital letters, the rest can be small case eg [demoplc]DB1,x0.0
The x can be lower or higher case but if you make the DB lower case the tag fails.
I’m sure I had set the tag to be in upper case in the first place but Im happy its working now.
Readrequest now shows up in the list.