I've just upgraded my dude server (CHR) to 6.47.4 and my Dude client to 6.47.4
All my links now show Rx: ? and Tx: ?. The links are using SNMP monitoring.
If I select a device and go to the SNMP tab and then the interface section, the interfaces are shown, complete with their current speeds, so it looks like the data is being collected, but not displayed in my map.