Today I decided to go ahead and try Logos 4 Mac for part of my devotional routine, which includes using a prayer list. When I was done using the prayer list, when I went to Logos 4 Windows for my studies I found that there had been some sync issues with the prayer list. For some reason, even though I didn't think I had done any editing of my prayer list on Logos 4 Mac, it had created two copies. 'My Prayer List' and 'My Prayer List (2)'. I deleted 'My Prayer List (2)' to find out that 'My Prayer List' was empty.
Anyhow, I don't know the exact cause of the problem and I don't have time to go back and try to replicate it, but I thought I would give the heads up to the developers that there may be sync issues. I noted as well that the same thing had happened to a handout as well. Another copied had been created with (2) in the title.