I can't pass getslides(string contextkey) to webmethod slideshowextender

After two days, no luck with this.

I have setup slideshowextender as:

                 <cc1:SlideShowExtenderID="SlideShowExtender"runat="server"TargetControlID="Image1"ImageTitleLabelID="lbltitleL1"

AutoPlay="true"PlayInterval="1000"Loop="true"PlayButtonID="ImgBtnPlay" StopButtonText="Stop"   

PlayButtonText="Play"NextButtonID="ImgbtnNext"PreviousButtonID="ImgBtnPrev" UseContextKey="True"Enabled="True"SlideShowServiceMethod='getimages'>

</cc1:SlideShowExtender>

And my webmethod code:

<WebMethod()><ScriptMethod()>PublicSharedFunction GetImages2()AsSlide()

Dim slidesAsNewList(OfSlide)()

        slides.Add(NewSlide()With { .Name ="test1",  .Description ="Kitchen", .ImagePath ="imageget.aspx?id=1"})

        slides.Add(NewSlide()With { .Name ="test1",  .Description ="Kitchen", .ImagePath ="imageget.aspx?id=2"})

        slides.Add(NewSlide()With { .Name ="test1",  .Description ="Kitchen", .ImagePath ="imageget.aspx?id=3"})

        slides.Add(NewSlide()With { .Name ="test1",  .Description ="Kitchen", .ImagePath ="imageget.aspx?id=4"})

Return slides.ToArray()

EndFunction

All this code works above, however, I want to be able to be able to change the "imageget.aspx?id=<value>" based on the userID.

If I use the contextkey and set it in the page_load event and then try to set the slideshowextender.slideshowservicemetod="getimages(string contextkey)" and then add byval contextkey as string to the function, it won't work!  Javascript keeps telling me the web method can't be found.  What is the correct syntax here?

Thanks a ton!  Would be great to get this working so I can pull images from database depending on user/situation.