I realised I hadn't set the .exe of the game itself to Compatibility Mode, only the launchers - did that and it works perfectly. Wrex is a pretty cool guy.
His conversation in the lift with Garrus on the way to the Normandy for the first time was good - "if they're on Saren's payroll, killing them is business, and if they're stupid enough to fight me anyway, it's a favour to the galaxy".