brandyriver

Ok I could use a little help, I tried everything I could and I still have 2 more things left to find. I think I need another ring and then what ever is in the red box. I don't know what to do with the cassette tap and the battery, whats the point of the empty cd case? I found the 4 digits but don't know what they're for either. I've all ways been able to get a puzzle over half way figured out but could never finish it. I would love it if you could help.