This resides more on the Max side of things than the Watchout side, but I kept getting errors in WO when I used the "udpsend" object. For some reason, Max was sending an extra comma a few bytes after the message. It was working, but it bogged down WO considerably with the error message. It turns out that "udpsend" formats all its outgoing messages as OSC, so that might have been where the extra comma was coming from.
Anyway, I switched to using the "mxj net.udp.send" object and all was fine.