Problem Solved
I too have had this problem.
The issue was that the driver’s door was very hard to open at times, and at other times it would not open at all from the inside [I would have to roll down the window and press the outside door release button to open the door]. Issue was worse after running the car and/or hotter ambient temperatures.
Apparently there were some slight variations in the positioning of the mechanism vs. the doors vs. cables which created a situation where the cable that releases the door was too long [or would stretch, which was worse with heat].
I was told that they made a change to the release mechanism at some point to resolve this problem.
While at Saleen, they replaced the door mechanism; problem solved. Door opens as it should, every time.
Be aware that before they changed out the mechanism [which included ne cabels], they told be that there was a Ford ‘engineering directive’ to reverse the cabels for the latch and lock inside the door to correct the problem. They tried that fix, but it did not work, so they replaced the entire mechanism. All works fine now.