Phew, I've hit another HTML issue.
I changed the way my login screen works and tied the 'jump to frame' event to a different event. I also added new graphics to the login screen. After doing so, the new background object I added is still visible after the frame jump, showing up in a frame which doesn't actually contain that object. Additionally, the focus is lost when entering the second frame. There is a 'start of frame' event which places focus in a list object. It used to work perfectly but now the up/down arrows just scroll the screen and the list wont regain focus.
Anyone else run into anything like this?