This update contains the following changes.
- Added progress tracking. All solved problems are marked with a checkmark in the list of all problems. (The show solution button must not be used.)
- Added support for fullscreen mode. You can press ALT+ENTER to switch the game into full screen view or click the "Fullscreen" button in Settings.
- Reworked descriptions of some problems.
- Simplified solutions to some problems.
- Fixed various smaller issues and typos