How do I import or specify which model to use?

[Hello-Linux]

I see we have four training models in our program, I use the command "python. \export.py --weights./yolov5s.pt --include engine --half --imgsz 320 320 --device 0" There is now a new official model yolov5s.pt, so how can I apply this new model?

yolov5m320Half.engine
yolov5m320Half.onnx
yolov5s320Half.engine
yolov5s320Half.onnx

The second question is how do I modify the following two parameters? screenShotHeight = 608
screenShotWidth = 608, and when I did, pytorch reported an error saying it could not exceed 320

The third problem is that the speed of my game's self-aiming has a certain time difference with the task movement, and always self-aiming fails, and there is another problem that if the enemy is far away from me, self-aiming fails, how to optimize it?