Anna,
I have done some testing but it still is not working. For 99% of our cases, it appears that a "Normal" disabled will have a value in userAccountControl as 0x202 (514 in decimal). I added a filter in the Dirsync GUI to filter out accounts where userAccountControl is set to 514. I also tried the hex value of 0x202 (see screenshots below). Shouldn't this take care of most normal disabled users?
Thanks.