We can then gather information about the issue and assess whether it's limited to certain computers, just a few people or a lot of people. Others may have a different opinion about this, but it would be interesting if you let us know whether this issue does occur each day. It's likely therefore, that you will see this the first time that you open your iTunes Library on any given day and the only current remedy is to let it finish what it's doing. It's my opinion then, that the reason that your iTunes was not responding is because it was busy making your cloud items available (even if, as in my case, that is not what it's actually doing!).
Note what tt2 pointed out about the cloud symbol it indicates activity of a similar nature to the 'making your purchases available' activity that I referred to.
