Kornhornio Pipes - Rotate the pipe segments to connect all the pieces. Features a resizable board, randomly generated puzzles, and auto save and resume. Easy to learn... and yes, every puzzle can be solved.
Moving the cursor - Directional buttons/joystick, or 2/4/6/8 number keys
Rotating pipes - OK button (usually in the middle of the directional buttons), or 1/3 number keys
Adjusting the difficulty/resizing the board - Select "Resize" from the menu
Zoom in/out - # / * buttons