You have to calibrate in window..otherwise Window won't recognize any signals for any games, sims, and etc.
FMS runs in Window. This is where you can calibrate a gamepad to act more like your TX....by taking out
the gain , adjusting the exponents or sentivities...because Gampads are more sensitive than a TX.

Then calibrate in whatever software or sim you're using.

Kind of like programing your Computerized TX. Another way to make a model less sensitives for new comers
is to adjust the gain cruve in your TX. Make the sticks less sensitive at center...not just the expos (max throw).
In a computerized TX..you can also adjust the expo only on one side of the stick. Very useful when adjusting the throttle
but also useful when you get a model that rolls more on oneside than the other.
In a none computerize TX, when you adjust the expos..it's for both side of the sticks.