Double click on it. It will automatically patch the original LR2.exe and install a required .DLL file (SSAPI.DLL).
What this patch is:
This patch enables LR2 to be played over the internet using TCP/IP and DirectPlay. Specifically, we've tested this using the matching service Heat.Net, and it works great! (http://www.heat.net)
What we did:
We've streamlined how the packets are handled. Originally the packet sizes were approximately 10k; while fine for a high speed LAN, it was unplayable over the internet (unless all players were on ISDN or faster speed). Therefore we re-worked the client-server model, and now pass much of the load that was formerly on the server off to the client-side. Now the packets are much more managable for standard modem users.