The feature comes in the new version 5.6 already available for download and is accessible when starting a new puzzle: Check that option before starting a puzzle.
The recovery of color is also reflected in the mini-image (if you have it visible) and the image of puzzle (the one you see when you press the space bar).
These puzzles are challenging and also rewarding. Try the B&W mode first with the easier options: For instance with the Non-Rotate option and perhaps an easy shape such as Drips. (But there’s also some help from the mode itself: If you join two pieces, as the image/mini-image shows the joined zone in color, it will be easier to guess the location of these pieces in the image).
You can create gift puzzles with the Black & White mode and surprise your friends.
More improvements in the latest new versions:
- Improved speed of internal processes.
- Bug fixes.
- We have been told that in rare configurations the program got stuck for a few seconds, nothing severe but it is fixed now, just in case you had that issue.