I've seen the same issue. I've been told it is an system issue with BOINC itself and not MW. Your preferences will update the next time you get work - stupid really, but that is the wisdom of the BOINC devs.

This was covered in a previous thread.

It is not a BOINC issue, it's an MW specific one.

The default BOINC scheduler behaviour is to issue a host record DB query every time a host initiates a contact session. The reason is precisely so the host can update it's local stat and global preference records.

However, in MW's case the scheduler has been modified so that if there is no work available in the scheduler's local queue, no DB query is issued. The host record query is only issued if the host actually gets a work assignment or it has work to report, because you absolutely have to in that situation.

You can test this right now over at SAH for yourself, since they seem to be having trouble getting work out the door at the moment (the scheduler is reporting no work available).

Tweak a global pref for one of your hosts, then do manual update. You will see the change is passed back to the host immediately, even though there is no work to send.

Alinator

OK. I stand corrected and take back what I said about the BOINC devs, but the action is short sighted and means that BOINC can't follow your desired set up until MW says it's OK.