Mark, your solution worked perfectly. I had tried your idea previously, but I set the field to a Formula Text field like an idiot. After changing the type to Formula User it is now working properly.
Matthew, I tested what you are suggesting, but I am unable to change the field type of the [Related Resource] to formula - user without breaking the previously established relationship and having it output the last modification to my user table itself. I also cannot change the [last modified by] field's type in the related table. I am interested in your solution as it seems a bit cleaner. I'm going to have to connect a lot of different tables to this one user table to monitor records/performance of users using summary fields, so not having to create mirror fields would be preferable. Would you be willing to elaborate a bit on your explanation of your solution? I assume I'm probably editing the wrong field or misunderstood what you said.
