Interface charts and gauges are reading values from ifTable (OID: 188.8.131.52.184.108.40.206) and ifXTable (OID: 220.127.116.11.18.104.22.168.1). Open MIB Browser gadget (in SNMP Tools folder in Workspace Studio) and read the two tables from the device. Check for columns ifInOctets or if OutOctets (ifHCInOctets and ifHCOutOctets respectively). Do they show any values? If yes, there may be an issue in Workspace Studio and I would recommend contacting our support.