To drive the cars with paddles or sequential shifting, you need to turn the dial on the G25 shifter to sequential, THEN change the settings in LFS from shifter to sequential. Then you need to assign the Up and Down shift buttons to either the G25 shifter OR the paddles.
I had the same problem with heel-toe until tonight
I decided to see the difference when racing with shoes, and I was pleasantly surprised to find out that heel-toe is ALOT..ALOT easier for me with them on
What I would do is put on auto-clutch... Then just brake with left foot, and blip with right until it is easy. This taught me how far to push the gas pedal and how fast to get smooth downshifts. After I started using auto-clutch but still clutching with my left foot and heel-toeing with my right. I'm still a total noob.. but getting better