I’ve also contacted Creality Support about this. They say that only the lower left corner is supported by the machine when using a USB Stick. They also said that the process to start the Falcon2 is to press the Frame button and then the Play button, both being required. I asked them to consider a feature where you can run the job without doing a frame (since it will go off in the wrong direction if you’re not using the lower left). I won’t hold my breath for them to make the change though.
I suppose a solution is to simply connect my laptop to the laser via a USB cable. I did some experiments with that yesterday but I didn’t find it really helpful. It may be the best option if I’m trying to do something tricky like avoid the head from running into a tumbler handle or something like that.