Congratulations on the purchase, below are some of the answers you desire
1) Check the fuse in the fuse box, if not, take it to an electrician to check its current that is flowing to it
2) probably a fused bulb, open the speedo, replace the bulb
3) Get one from Shershah, remove this and put that in, its a simple task, just get one with a similar connector
4) Plugs, filters, oils, thats it.
5) Again, simple task, go buy a cd player of choice and they install it for you
6) Take it to the excise office, take the fellow along, pay the dues and get it done