Baffled by Logi Flight panel setup

I foolishly thought this thing would just be a case of plug and play - jack it into a USB port, then map controls via DCS in-game settings.

Oh boy was I wrong

I've just spent an hour jumping through hoops to get it working, but several issues show up. When I start up DCS flight panel, I get this error:

https://imgur.com/a/74lsqiU

Yet I've installed the DCS BIOS into the exact directory specified in the readme. However, I haven't installed the Arduino software, as I couldn't find any instructions on why or how to do so.

Once that error has passed, I get into the config screen proper - but none of the controls I map work in game. I'm starting with a simple one, landing gear up and down, but no dice.

Please help this poor sod out, as I'd hate to think I've wasted AU$175 on this.