What happens if you simply save the settings from the Options page? Also, where do you see this error?
The behaviour I would expect, if there was an error from the callback file, is that the template modification would not be applied (and so you would not see an error at all, because it wouldn't be applied).
Let me know.
The behaviour I would expect, if there was an error from the callback file, is that the template modification would not be applied (and so you would not see an error at all, because it wouldn't be applied).
Let me know.