A few questions:
1. Do you already have MPTS installed?
2. Do you already have TCP/IP installed?
Assuming the answers are yes to both, then you can get your Realtek driver installed.
The first step is to unzip the driver for your NIC into its own directory on the hard drive.
Then start up MPTS - open up a command prompt and type: MPTS
You'll be able to go into "Configure LAN adapter and protocols" from there. Click on the "Other Adapters" option, and type in the path to your driver, hit OK.
It will copy over the files, and your adapter should now appear (see cautionary note below) somewhere on the list of network adapters that you can add to your setup. Add the network adapter and then add the needed protocol (tcp/ip usually, maybe also netbios and / or netbios over tcpip)
Cautionary note: Due to a bug in some of the older versions of MPTS, sometimes the network card won't appear in the list of available cards after the first time you use the "add other adapter". If this happens then repeat the process of adding the adapter - it generally shows up on the second attempt. As far as I know, IBM fixed this problem in newer versions, but earlier ones (including the MPTS included in the base Warp 3 connect and the base Warp 4 release) you had to "add" the card twice. I do not believe this is a problem on any release of eComStation.
Another comment on the Realtek cards in particular - I've used quite a few of these cards over the years, and find them to work very well under Warp. However if it is a RealTek 8029AS based card, there is a newer (better) driver on Hobbes that fixes some longstanding bugs. For other cards, the drivers on the RealTek site seem to work
Once your card is installed. run the TCP/IP setup and you should be able to configure your card.
Hope this helps.