ELM data, as of current, is primarily used as a support for the parsed events that are in the ESM that are used for correlation, reports and populating the views. Watchlists are used to filter against the ESM data also. All of the interesting data, like usernames and IP addresses are parsed into the fields that are filtered by the watchlist. The fastest way to apply a filter is to use the Global Filter boxes on the right side of the view. You can click the Filter icon and select a watchlist to apply to your view. Reports work in a similar way and creating a table with the required fields filtering the source user for one table and possibly another table filtered by dest user.
With the next release the ELM should see some new functionality but it shouldn't be necessary for this use case I don't think. Thanks.