Ok update here on the keyboard button combinations issue. Recently the AX370 became even more limited and couldn't even get 2-button combos to work! For example, right+space would cancel right.
That was totally iffy and made me think the situation is a deterioration. I dismantled the machine and blew out the keyboard keys. The plastic membrane under the keyboard was in excellent shape. The motherboard looks perfect too. I tested the keyboard membrane by plugging it into the computer without the actual keys. To my surprise, it worked perfectly even with 3-button combos! So the issue is not a BIOS issue. Something wrong is happening and causing this behavior.
I put back the computer and it still works great. I don't know what really fixed the issue in the end, but I won't complain 
So...myth debunked. AX-370 has no keyboard issues from the Arabic BIOS!