I'd post this same Q in Safety razors. Rollsshaver and a few others can give you all the ins and outs of them. I will be looking at the post as I have a Rolls razor headed my way, finally.
I have had good success using natural bees wax on my Roll's strops.If you can get your blade sharp enough,the resulting shaves are good,albeit not quite as close as D/E or S/E shaves.
If you want to use a chromium or diamond paste on your Rolls blade, don't put it directly on the strop. Instead, get some medium weight watercolour paper, cut a piece to size and give it a light layer of the paste, lay it on top of the Rolls strop and strop as you would normally. It works a treat.
I just took one of my old Rolls razors out of hibernation and shaved with it.
Prior to shaving, I removed that guard, and stropped 20 or 20 passes on a green pasted HandAmerican flatbed strop followed by the regular Rolls stropping. I had quite a smooth shave.
I does amaze that this old, yet beautifully engineered gem is quite capable of good shaves. Sure is a pain in the #*###! to use however!