this fuel issue worried me as well, so tommorow I'll pick some fresh gasoline mix it with the conditioner I have and let it work it's magic.
Brakes - lever for the front was broke so I ordered a new one today. Fluid will be changed ASAP. Otherwise both seem to work - still I believe brakes are the most important part of the bike so as soon as i get the chance, I'll disassemble and check them.
Tires - mixed bag here. Those seem to have seen little to no use, but IIRC tires have a predetermined lifespan whether driven or not. Will be checking them carefully for cracks etc.
Chain - slack is according to the book. Will be oiled and checked once again.
I waited will all the work around it for spring to come, and secondly wanted to invest the overhauling time first when I'm 100% sure it works. It does
Getting it under control will take time, so as of now I plan to get some basics in starting and stopping and maneuvering on 1'st and 2'nd gear, then gradually work my way up as time goes by. All my experienced friends already warned me - ca. 47HP for first bike is dangerous so I'm cautious.
The only training facility I know of is my Brother In Law