I have made a drawing of what i require but i have tried 3 ways and so far not managed to get it right.
The problem i have is a step.
Basically it is two squares like a photo frame where on the inside of the frame is a step in each corner.
What makes it harder for me is the step is 1mm thick where the rest of the frame is 2mm thick.
My last attempt was to create it in 2 layers both 1mm thick and now not sure how i place one ontop the other so i can print it as if i group it the top layers sinks into the bottom layer and only gives me 1mm thickness overall.
I noticed that the radius option had gone but double clicking one shape i was able to apply1.5 i then tried to do the same with the other layer but i cant apply a radius to it ?????
See my work flow image please.