Castle of Elite - Official game guide|
Introduction - Basics - Solutions - Secrets - Trivia
When the guide tells you to place a brick symbol on a certain square, it means you should aim the mouse cursor on that square.
1-8: Beware the Trundler
A: Get the symbol and place it here. Wait for the Trundler to pass.
B: Get the next symbol and place it here.
C: Get the last symbol and place it here, crushing the Trundler.