Aglavalin is right: there is some sort of bug in the config page that is setting variables to zero. Here is what happened to me:
1) I set the option to not display the initial instructions (the changes to the templates, etc.) so that it would not display when I went into the editor.
2) Now when I make a change in the editor and click on the button at the bottom of the page to save the changes the variable that should be set to "0" for displaying the initial instructions is set to nothing and I get a pars error when my index page loads. Manually editing the variable (adding the 0) fixes the problem.
I've even had all the variables reset to nothing, but that may have been due to a poor connection with the server when I was trying to update the page.
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