I have created a flying logo that I want to use for an animated button in Arch 5 - is this possible? I know I can create an animation right within ARCH 5 using keyframe, but what about one that moves on the screen that is created before-hand?

Generally speaking... render out a video the way out want the menu to behave and then use that as the menu background. You can use delayed buttons so the buttons don't appear until the actual background for the button is in place.