I just completed this replacement door handle on the left side (driver's US) and I have some current details. The internal "carrier plate" panel is a bear to remove. I also did this recently to replace the temperature sensor under the right side mirror. After releasing all 10 of the white plastic bayonet locks with a 13mm socket / spanner, you also have to pop open 2 rubber caps that look like lens covers on a pair of binoculars. You will have to reconnect the window controls, (battery still connected as well) and lower the window about 3/4 down until a 10mm bolt head appears in each of the openings where the rubber caps were. Loosen the 10mm bolts, about 4 turns, but do not remove them. Grab the top of the glass and pull up firmly to release the glass from the carrier. The internal "carrier plate" has the window mechanism attached to the inside of this carrier plate, so the glass must be removed to separate the carrier plate from the door. I have puled the glass up manually and twisted it so the front of the glass rotates down. The glass can be lifted out of the opening slot while rotated 90º. There is also another fastener behind the door speaker that attaches the forward window glass track to the carrier plate. The bottom of the carrier plate must come out first as the glass power track goes above and below the steel inner door frame opening.
***CAUTION*** there is a side impact sensor attached to this carrier plate. It has yellow tape wrapped around the wires connected to it. I have not removed the harness or removed this sensor and leave the carrier plate's cables attached and just move it aside. If you do want to remove it completely, disconnect the battery and allow the system to discharge for at least 10 minutes. You really don't want your airbags going off accidentally.
A note on the pictures from the original post from ncng. On picture Fiat 1.jpg, the torx screw behind the rubber cap on the side of the door, is not a removable screw. It is held in place and rotating it just slides a small steel plate "finger" that secures the lock mechanism to the door frame. It is reverse of a normal screw, meaning clockwise retracts the locking plate, and counter clockwise re-engages it to hold the door lock in place. To remove the door lock, you must turn it clockwise as if you are tightening a normal screw.
I hope this helps future door panel removers. The plastic bits that make up the external handle skin appear to become brittle with age & heat. So I'm sure this will continue for some time. The internal ABS plastic parts of the door mechanism are much more robust. But that type of plastic probably cannot be coated in chrome which I believe is required to have the capacitive door unlocking feature function.