The HTTP interface, where you receive a request and are writing to %print_fn with the html (or xml or json or whatever) that you want to return... does it have to be Apache? In the documentation there's clearly scripting info in a .cgi file to say start PxPlus and runs *plus/apache/pxp_cgi. Is there anything in there that requires Apache rather than a different web server? For example, could I have an equivalent script in IIS that runs PxPlus *plus/apache/pxp_cgi and it will forward the web request and return the response to IIS?