Hello, is it possible to let users decide what size they want the video to be they upload instead of that pre-determened size in the Media Manager? When people upload for example video's in HD format (720) it doesnt display correctly. I just wanted to know if it was possible instead of having it hardcoded in the ACP.

Not presently. It's something I've thought about, problem is I can easily see users abusing this and setting display size to, for example, something like 3000x2000. Most likely I'll implement this at some point, I just have to outline proper controls for it.