For those having problems with their WS1000 USB Wireless Simulator Dongle from Spektrum, I finally got it working with the FPV FreeRider program. Here are the changes I had to do in my transmitter (Spektrum DX9) to get it working:
I hope it will help somebody else.
First, create a new Acro model (Airplane).
After it, go into menu "System setup | Channel Assign". Here is configuration you need to set:
Rx Port Assignments
=================
1 THRO: Throttle
2 AILE: Inhibit
3 ELEV: Gear
4 RUDD: Rudder
5 GEAR: Elevator
6 AUX: Aux 1
7 AUX2: Aux2
8 AUX3: Aux3
9 AUX4: Aux4
Then click "Next" to go at the next screen
Channel Input Config
================
1 Thro: N/A
2 Aile: N/A
3 Elev: N/A
4 Rudd: N/A
5 Gear: Ail
6 Aux1: B
7 Aux2: C
8 Aux3: D
9 Aux4: E
Finally, go to menu "Servo Setup | Reverse" then reverse following channels (See also pictures attached). This part is nor mandatory but it will prevent you to reverse channels into the FPV FreeRider program:
THR
INH
GER
RUD
ELE
Good luck!