"Something in the template's gone sour" says that some edit, somewhere, has gone screwy.
With PHP, that can simply mean that there's a bloody comma in the wrong place, or something THAT trivial, sadly.
You could always replace all of your files with virgin copies.
Obviously, you'll lose your edits and things, doing that, though.

Maybe try replacing everything in "Sources", first, to see how that goes?
Read my sig, first, though, so you're covered.
