SnmpWalk uses SNMP get-next command to get the first variable of the requested range. Thus, the first variable is the result list is not the one requested, but the next one (which OID goes immediately after the requested OID).
Example: SnmpWalk.exe -r:address -os:220.127.116.11.18.104.22.168.22.214.171.124
This will produce results from 126.96.36.199.188.8.131.52.184.108.40.206, and not from 50 which is what you'd expect.
Affected Version: 1.02
Status: Planned to fix