No such thing as a B66U.....it's either an 'N66U' or 'AC66U' or 'AC66U B (the latest rev just released)'
For the first two, load the latest stable release.
For the last, it's not officially supported (see many threads on the AC66U rev B). Some have had luck loading the latest Merlin AC68U code, but AFAIK nobody has tried this with this fork and I suspect the fork code will not work.
Its A N66U running fork V.14.1
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