NitroJonnyD - You can solder the schottky diode on the motor wires right before they solder onto the motor, the closer the schottky is to the motor the better. If your GT-7 came with a big black square shrink wrapped on your wires then you do not need to use an additional schottky diode. The red stripe side of the schottky goes on the positive wire.
PTP Racing - If you change your profile on the speedo it will not hurt anything, worst thing that will happen is that you will need to cut your motor a little more often if you end up running a lower drive freq. About your radio needing to be 111% throttle, don't worry about it, that's OK and why Novak has that function in the speedo b/c radios can differ from one to the other.
Drive Freq - Higher number makes throttle smoother and will have better top speed, don't need to cut comm as often as with lower freq. Lower freq number gives more punch or acceleration, less to pspeed, motor needs cut more often.
Min Drive - Higher number will make it more punchy initially when you hit the gas, lower will be smoother. If you have Mind Drive set at 2% then the car will receive 2% power from speedo before it moves, it if's higher like 50% then the car will start moving with 50% power like if you were to pull trigger back 1/2 way then drop car onto ground.
Brake Freq - Higher means smoother and lower means not as smooth, I like mine turned up so the brakes are smooth.
Min Brake - Same thing as Min Drive but for the brakes, if set low brakes will be smooth, if set higher the brakes will be too punchy and can make car spin out.