As far as I can tell...
8 letters in the rack as standard, unable to place bonus squares (of any type) in the same position on all four diagonals (e.g. 1 in, 1 up from each corner, or 2 in, 2 up etc.)
Any game in progress on a now disallowed board layout automatically had the board changed to "WordScraper Standard", and the nature of the changes wasn't spelled out to users (only the fact that the changes had been made as part of the settlement)
Apart from that, the same customisation levels as before - i.e. able to place 4x and 5x bonus tiles in addition to 2x and 3x; place bonus tiles where you like (apart from the positions mentioned above); able to change the distribution and value of letters; and able to choose different styles of board (square - aping the original, circles - original, and 'midnight black' - effectively a negative version of circles).
Interestingly, two features which WordScraper didn't initially allow appear to be OK under this ruling - tile values printed on the tiles and blank tiles.