Can't find graphedit filters

[Letricheur]

This is probably a crazy newbie question but I can't find the filters in Graphedit. I am following the graphedit guide on this website. I first render a video file, which generates the graph. I click File - New - say no to save changes and the graph disappears. I click Graph - Insert Filters, and.....nothing happens. No filter dialogue box appears. The SysEnum program shows me plenty of registered filters but I cannot get them to appear. If I try again immediately after the graph is generated by rendering, still no filters.

Am I missing a crucial piece here?