Well, you took away the usual suspect - new skewer in an old frame. And you can't blame it on chrome. I'll say - the dropout is Bent! Actually, I got nuttin'.
You might look at the axle locknuts, since you're considering changing the spacing. Are the nuts flat, or do they have a ridge or any feature that might keep them from slipping? Sometimes these get reinstalled backwards.
An old French bike may have had the old style dropout inserts instead of adjusting screws. I see these every now and then. maybe loosescrews or yellowjersey might carry them.