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X_Axis = SAR_ADC_GetResult16(0) *0xFF /0x7FF; /* Get ADC reading and store in variable X_Axis */
might not give the expected result due to overflow and intterpretation of 0xFF a positive or negative number. Write 0xFFu for unsigned.
You did not tell what errors you have got.
BLE is not compatible to "normal" Bluetooth.
Here is a program that moves the time around the screen. I think you can get an ideal about the Joystick from this program. It will need to be up graded to the latest component revisions however.