Chris and I have actually been corresponding about this issue, which he had also come across since writing the article. The Third Party Extension Buttons checkbox turns basically off Java and Flash, rendering a large number of web sites unusable. So in general, I would think almost everyone will want this setting to be off (it is turned on by default if you choose the high security option). Our one question about this is wheter it applies to both IE6 and IE7. Which of these are you using?
We will update the article to reflect this and recommend unchecking the option.
FYI - for others reading this, Chris Peters at the WA State Library has recently written a <a href="../do/DisplayContent?id=17759">detailed guide for using SteadyState to configure a library public access computer</a>. This is in addition to the general intro article you can access over on the left rail of this page.
Dale
