Hi Robin,
You can configure Application Name, Tier name etc for .NET as well, please see below for a sample config file that I have using for .NET.
<?xml version="1.0" encoding="utf-8"?>
<appdynamics-agent xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<controller host="HOST_NAME.COM" port="8090" ssl="false">
<application name="APPLICATION_NAME" />
<account name="customer1" password="password_here" />
</controller>
<machine-agent />
<app-agents>
<IIS>
<applications>
<application path="/Appname" site="AppSite">
<tier name="TIER_NAME" />
</application>
</applications>
</IIS>
</app-agents>
</appdynamics-agent>