Louis, Thanks for voicing your concern. I am going to see the Doctor today as it has been nothing but pain for the last 4 days. No bruise visible any more, but it hurts day and night.
You are correct about the not rushing back to work. I have been going to the office but I don't think that has been smart, either. I need to give it some time to heal.
Funny you should log on as I was just thinking about you yesterday!
The hardboard will not curve to a 20" radius, maybe 40". However, the laminate material they use for countertops, sometimes called formica, will bend down that much and is plenty strong to support a backdrop. It can be custom ordered to your dimensions and attached easily to adjacent wood using contact cement.
Masonite--could be the same stuff.