Q3,Q3:
try to learn some scripting and learn how to use panels I think this are the best ways to start a cool Menu
Q1: put the moddel in the work folder
then -> rmb -> add -> add moddel and then playe your moddel
for the script: -> file -> Map properties -> script ->create new script now you can choose between templates or an emty one
hope this helps so far
Regards
Aztec