PLEASE post pics of the amp!
You can keep the guitar in the case, but as I said, the humidity is important. Anywhere from 30-50% humidity is great. Honestly, with something that valuable it's worth it to check that kind of thing. Guitars also don't like changes in humidity, so try and keep it fairly constant.
In terms of storage, I would probably keep it in the case so as not to sustain further light damage. Light, over time, damages finishes on wood. Also, do NOT keep the guitar case laying on its back (e.g. under a bed), either stand it up straight as if the guitar was sitting on a stand, or leave the case on its side with the handle facing up.
I'll be happy to answer any other questions I can, I'm not an expert but am fairly knowledgeable.
Us And Them - The Pink Floyd Experience
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