Configuring and using the WSRP web part in Office SharePoint Server 2007 is not well documented (I couldn't find anything at all) but luckily I saw a thread on the subject on an internal technical discussion.
First you have to create a TrustedWSRPProducers.config file in the :\\Program Files\Microsoft Office Server\12.0\Config\ directory. There is a sample template file called TrustedWSRPProducers.xml.sample
To use the demo netunitysoftware provider, place the following in your config file.
<Configuration xmlns="http://schemas.microsoft.com/office/sps/2005/WSRP/Configuration" ProxyAddress="http://Your_Internet_Proxy:80">
<Producer Name="NetUnity" AllowScripts="true">
<ServiceDescriptionURL>http://wsrp.netunitysoftware.com:80/WSRPTestService/WSRPTestService.asmx</ServiceDescriptionURL>
<RegistrationURL>http://wsrp.netunitysoftware.com:80/WSRPTestService/WSRPTestService.asmx</RegistrationURL>
<MarkupURL>http://wsrp.netunitysoftware.com:80/WSRPTestService/WSRPTestService.asmx</MarkupURL>
<PortletManagementURL>http://wsrp.netunitysoftware.com:80/WSRPTestService/WSRPTestService.asmx</PortletManagementURL>
<!--SsoApplication Name="NetunityWSRP"/-->
</Producer>
</Configuration>
You may also need to set the Internet proxy settings in your web.config file.
Then add the WSRP web part to a page and edit the web part properties which are self explanatory.
The demo below requires you to be logged in from the Welcome menu at the top of the page).
Use corp\demouser password: pass@word1