It is programable through the "GK6XPlus Driver" software, which is what most of the complaints about the software being bad are about. You *can* reprogram everything except the "Standard" layer and the FN key on the other layers. It's just not amazingly intuitive. And the scaling is weird on a 4k monitor. (*edit* it is NOT compatible with QMK/VIA)
If I program this on my PC can I then use it on my work laptop without downloading any software onto the laptop?
will I be able to use the programmed macros on the laptop?
I think you could use it sideways, your hand would only rest at a slight angle. The only down side i could see is that it's relatively thick (tall) so you'd probably wish for a wrist rest or something, my hand wouldn't be comfortable at that angle for long.