IF I let my CLZ subscription lapse what happens to the data I’ve entered?
Nothing really 
So it will not vanish? But I will simply NOT be able to enter any new data, correct?
That is correct.
Which product are you using?
I am using CLZ Books, Movies, Music (iPhone) and Book, Movie, Music Connect (iMac).
Was asking for a friend who’s looking for something to organize books, movies, music.