The GHcloud can be a bit intimidating at first, though there is a fair bit of information on the forum regarding how to use it.
I am sure other around would be able to answer deeper questions about it
If that is a bit much to start, coinprism also has a fairly simple color aware web wallet that can be used (and the keys to your wallet can be imported to both so you can access either way!)
GHX represents 10 GH of whatever equipment is currently mining in the GH DC.
Today they are S5s but could be something else like S7s in the future.
Based on the current sales of B3, it looks like it will be more than a few weeks until S7s are brought online and the team may instead go with smaller batches to start the process of swapping out slowly instead of in mass.
The total # of GHX depends on the current machines online hashing.
For example, as a number of machines were DOA after our last move, the team did a controlled destruction of GH owned GHX to reflect that since the hashrate was not usable.
New tokens will not be created until equipment of an equivalent hashrate is brought online.
Other than the scenarios you mentioned, volatility of bitcoin is always an issue.
Should it drop significantly for an extended period of time, most operators in the business would be operating at a loss and close down in mass.
Outside of that, should the operation fold I believe there is something in the TOS on hardware redemption for owners since the concept is everyone who owns shares actually owns the underlying hardware (including the GH team same as everyone else)
I'm not sure if that answers you questions, but feel free to ask away