Cutting those areas wasn't too bad. Sensors - I was able to slot the knife between the sensor and body panel so I didn't need to cut on the panel of the vehicle. Door handles - I was able to get the film lifted off the handle and make an access cut along the centerline of the handle. From there I was able to get the film lifted off the handle recess, put a slight bit of tension on the film, and then make my cut off the panel with the blade hovering over the gap between the handle and the body panel.
I found one of the keys to getting the blade to glide and not catch up on the film is to make sure the area being trimmed has a bit of tension.
The pros can cut on the vehicle by scoring the film without actually pushing the blade all the way through. I didn't even attempt that because I didn't want to risk cutting my paint. I was always able to find a way to make my cuts off the vehicle.
Edit: probably also worth noting is I removed as much of the trim as possible. Door trim, wheel arches, pillars, also removed tail lights, etc. That took some time up front but allowed me to tuck the film in those areas - easier trimming and seamless edges.