It's very simple to program your XCAM with a new fresh firmware

Before start let's check the configuration.

Addon inside CAS2, CABLE connected from ADDON and Dummy Card, the card inside the XCAM and the cam inside the decoder.

Now we have to put the XCAM in virgin state, if this is your case you can see on the cam menu of your decoder the "XCAM MODULE" message

If you already have a firmware you have to write a .key file on block 2 following next point and then restart the procedure.
To come back from a firmware to a visrgin state you have to go on the cam menu and chose the option to update your cam using the serial cable.
Now chose a .key file and press start programming button, then press ok button to start uploading on the decoder.
Aftre programming restart your decoder and you have to see on the cam menu "XCAM MODULE" title

Now you have to chose the file you need and simply press START PROGRAMMING and wait some minutes...

Enjoy