1. This has been mentioned a few times. Fences overrides wallpaper selection on secondary monitor.
2. Fences does not handle resolution dependent icon positions for icons not inside fences. To make it worse, it will not allow any other application to do it either. If I try to restore icon positions using another application, Fences moves those icons back to the wrong position the second I click the desktop. Ideally, Fences would handle icon positions for all icons, not just fenced ones.