I am too, dealing with a few issues with the mirror client on my Macbook.
Downloading the official Osrs client on mac its pretty patchy work as is.
This link below were the steps i took to get a seperate osrs client working.
(This is not my video)--- Also used legacy client to patch the "P.list"
However it gets worse, although i have a perfectly working client with no mods/injections; mirror mode cannot ("search" ) find another client.
My best guess for a solution would be these two options.
1) Find a way for the user to apply the ("Search/Hooks") to a client using a GUI.
2)Allow the mirror client to Patch around the fixed screen issue. (i believe it does not function simply because of the side widgets of osbuddy client)
Thanks for the read.
P.S. I hope this gets fixed soon, or there is pretty much no point for me to pay for VIP.