What i found is that if your using a 56k modem on a dialup, if you set the number of connections too high, you will lose control of your processor and it might freeze up.
BUT if you set the connections starting at 1 min & maybe 2 max it seems to work great!
Try that to start and see how you go. If its not locking up increase the connections a little bit (1 at a time)
Even if you start at 1 & 1 it will work.
Also sometimes you have to wait at least 5-10 mins for enough hosts and messages build up.
HTH