Hi,
in the last svn commit 378 I implemented a global pause and a inter char pause. The defaults are 0.25 secs for global pause and 10 secs for inter char pause. Global pause is the time between two single fetches and inter char pause is the time between two character updates.
With these values i was able to sync my own and one US guild completely without any errors. As the conditions vary from host to host you may need to play a little with these values.
Let me know how it is doing and witch values you tried. Make sure to do a break if you run into the filter.
If you still have problems let me know your values and what kind of host you are using(dedicated, vps, own ip, what so ever).
As I already made some changes for the latest template system, so this build is available from svn only and requires WoWRoster > svn[1722]. With the next nightly build i will pack another archive for non svn users.