If you look at the thread, in the top right hand corner somewhere is an icon for options. Click on it and one of the options is to switch to Linear+

Does this mean the board can operate in a modified form of ancient Cretan Greek (c.f. linear B) or is it something else??

I don't know, but if the board can't operate in a modified form of ancient Cretan Greek I shall be sorely disappointed and may have to take my business elsewhere.