Webpage sets the URL where you can access the log. The path needs to be set from the same location as where your ConferenceRoom Java Client resides. This command doesn't take a full URL; it only takes path names and should always end in .htm or .html.
/as log ConferenceRoom webpage mylogs/conferenceroom.htm
You should probably make the webpage name the same as the log name plus either .htm or .html. This will make your logs easy to find and keep track of. You might want to consider putting your logs in a secure directory.