I would like to know a few things though; Does the fuel truck have any animations?
Not really, it will just arrive, stay there for a while and go away. We plan to improve the fuel truck a lot in future versions, because it's one thing we aren't entirely happy with in GSX...
Also can I re size the selection windows when asking for fuel, catering and others? I am running at dsr 4 k and those windows get really small.
Unfortunately, that's something entirely outside our control, because it's a standard Simconnect menu. You can resize it, but only the windows size will be resized, the fonts inside cannot be enlarged.