Controlling a Sky box (or Roku Express) with Humax RM-F04 or RM-F01 remote

Does anyone know if it's possible to control either a Sky box or a Roku Express (the one with an IR remote, not a bluetooth one) with a Humax remote and what the code might be?

(I actually want it for the Roku Express, but I'm asking about the Sky box because it has the same code on a universal remote that I own, so I assume they both use the same IR codes)

I have both an RM-F04 remote with the three digit codes and an RM-F01 remote with the four digit codes.
I think I've been through all of the codes listed for Sky in the manuals for the RM-F04 and some for the RM-F01, so wanted to check if anyone else had any success before trying the rest with the RM-F01 and retrying the RM-F04.

Thanks in advance

P.S. I've searched all of the forums and not found anything useful