Hello All.

I have a large sheet metal panel rolled to a diameter value.

In the formed / rolled state in the model, I have projected circular Curves / sketches from the top plane up and, onto the rolled surface then created "Extrude Cuts" through the Panels for a true representation of what the flattened condition will be after the panel has been rolled.

The problem I am having is at the drawing phase. Because the thru holes are neither, round or slots more like obrounds. I cannot seem to be able to select any of the circular edges in the drawing for dimensioning purposes, I can't even place center marks. I have tried inserting Model Items but the critical dimensions I require do not come into the model view. When I attempt to select an edge this is the prompt I receive  is "The Selected entity could not be converted into a line or a circular arc"

My question is.

Does anyone have any recommendations as to how I can apply dimensions in a Flattened Drawing View to entities that are neither a line nor circular arc?