I discovered that discovery does not work because apparently the device returns a different OID.
On discovery it returns the following OID:
snmpwalk -On -v1 -c CsmsRO 192.168.0.30 .1.3.6.1.2.1.1.1.0
But Check_MK seeks the following:
snmpwalk -On -v1 -c CsmsRO 192.168.0.30 .1.3.6.1.2.1.1.1
Is there a way around this?