the zoom is handled quite confusingly atm. Read here to get some clarification, what makes it so weird:
http://forum.irexnet.com/viewtopic.php?t=548&highlight=
And panning is quite easy. Click on a point of the page, and drag it to some other place. Thats where it will end up. Thats nice.
@scotty: read the suggestion on the iRex forum, there is a description of a "page width" mode.