I had this same problems for months, notes would not show, as screen was blacked out (win7, 64-bit). I tried everything; uninstalling repeatedly, using different download sites, plus several other without success. Additionally the program constantly kept syncing causing the laptop to rev high and warm up. Was getting close to abandon the program altogether. In the end, after reading this thread, I did try disabling the 'enable hardware acceleration' option (General), it did not work right away but did after I also disabled 'synchronize in the background' option (Synchronization). Now all is fine, but this is strange!!??