Example. Items:
1
2
3
4
5
6
7
8
Click 2. 2 is selected.
Shift-click 4. 2, 3, 4 is selected.
Ctrl-click 6. 2, 3, 4, 6 is selected.
Ctrl-shift-click 8. 2, 3, 4, 7, 8 is selected. 6 drops out of selection!
Sublist indexing is tricky

Edit: looks like this doesn't apply to all selections. I'll try to reproduce it, and post back.
Edit2: this is the case when selecting from the "Details" view. Not the case when there are any artworks showing. And thanks a whole lot for the wireless synchronization -- it works wonders!