If you are operating in one-arm mode, it may be a feature interaction with SNAT. Since SNAT is never needed in one-arm situations, try turning this feature off in System Configuration > Miscellaneous Options > SNAT Control. This controls whether LoadMaster NATs connections using it as a default gateway. This can be necessary in two-armed configurations but it generally presents a problem in one-arm deployments.
Transparency pertains to how LoadMaster forwards traffic to real servers. In transparent mode, LoadMaster will pass along the original client's IP as the source IP. In non-transparent mode, LoadMaster will NAT the requests to the real server with LoadMaster's virtual service address. In order for your server to see the original sender's IP, you will need to operate transparently.
If you have one-arm setup on your LM, disable your SNAT. This will allow you to access your real servers via RDP. To disable SNAT, in the WUI Select the System Configuration > Miscellaneous > Network Configuration option. Uncheck the Enable SNAT checkbox. If you have a two-arm setup on your LM, create an RDP VS.
If you choose to enable L7 Transparency within a virtual service, the packets travelling from the LoadMaster to the server will have their IP source listed as that of the client IP. This will enable your servers to log the IP address of the individual requesting clients.