If you click on a cell in the game grid, an box and Update button will appear at the top of the button.
Put a new value in the box and click the Update button to update the grid.
For Puzzle X2, enter the 2, 3 and 5 to make the top left box look like
-1-
2-9
-53
The Solve button will then finish it.
Version 109
Allows you to save a game (in memory, not disc) and recall it. There are 4 save locations
Version 108
Puts back the error checking and turns faulty cells blue
Version 106
This allows you to input puzzles (press "Clear puzzle" first) and help it along as in earlier versions.
The solve button tries everything in one go until it solves the puzzle or gets stuck.
It can solve all the puzzles here except X1 and X2 (the "extreme" puzzles)
With X1, it works if you 'Solve' then change the 25 in the bottom right to a 5!
By hand, after 'Solve', I've tried the previous "trio" rule.
The top left box has only got 5 in its middle row, therefore
the other 5s can go from the second top row. I tried this through the whole puzzle.
It removed a good few digits, but didn't find a solution!
It obviously needs a different type of rule to solve it. If you can solve it, please let me
know what you did - and why.