So I pulled my RS22 out and confirmed what I was telling you was correct, and it is.
In order to release the bolt from the locked-back position with an empty mag inserted, pull back on the bolt lever with your left hand while pushing down on the magazine follower with your right hand and ease the bolt over the top of the follower as you remove your finger.
That's the only way to close the bolt without removing the empty magazine.
Here's my RS22, with a few modifications -
I've done some plinking with it, but really would like to try some different match ammo to see what it's capable of.
Also added some weight in the buttstock and forend.
I may work on the trigger next, as it's about the worst of any rifle I own - and I've got some old rifles that ain't that great...