People have reported similar errors, which turned out to be caused by some misconfigured elements.
I presume you're using a trial version, correct? Which edition are you trying out - is it Standard, Professional or other?
How many pages do you currently have and does this error occur with only one of them or all?
Information about what widgets you have on that page would help, as well as if you have set any permissions over them.
Grisha 'Greg' Karanikolov
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