Congrats on your new arrival. Buiding the edge was actually real fun. When it comes to hinging (pay attention, or your end up looking what my aileron did on the page before). When it also comes to gluing the joiners in take it slow and make sure everything is straight. When its says to dry fit, do it a couple times and double check that everything is straight.
You can go ahead and use ultrakote for some little designs on the plane. The lower heat setting of the ultracote will be fine with the covering on the model. Dont directly heat the stock covering or you risk damaging the stock covering. Make sure your heating the ultracote not the rest of the covering. I used clear ultracote to seal my hinges and it sticks fine with no troubles.