What is a Q.R race ?

Qualified Riders, in our terminology amateurs.

its for qualified riders only, ie amatuers

Strange - you'd think that would make them 'unqualified'.

Same with 'regulation fences' where the logic would lead you to think that these were standard fences (rather than open ditches)

You can see why some of the Irish (and British - before I'm accused of being racist) jockeys get confused with the concept of rules...