Oh, you absolutely can start her up with just mouse and TM HOTAS Warthog. After activating engine crank, you have to wait for spool up to around 25%. Then you have to advance the throttles past their idle detents. On the TMHW throttle quadrant, retreating the throttles past the detent is achieved by lifting them and dragging back. This works as button press button #29 and #30 left and right throttle respectively. Bind button #29 to "Throttle (right) - OFF/IDLE" and button #30 to "Throttle (left) - OFF/IDLE". Now when starting, you need to have the throttles behind their idle detents, and after cranking, you advance them, and the engine should ignite.