All overwrite the destination collection). Do I have to purchase SuperMemo 2004 in order to be able to have only one collection instead of several collections?

You do not need newer versions of SuperMemo to merge collections. The operation is only slightly more cumbersome. More.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.