Thanks for the feedback! Originally, the right click worked just like you said, but then I couldn't both display the preview of the object that can be placed by left-clicking, and highlight the object that can be deleted by right-clicking (or at least, it was a mess when placing a wall, and I thought it could be misunderstood). I want the player to be sure about what will happen whey they click on the puzzle. However, now that I think about it, I could make it an option in the UI settings (same as hiding the controls hints) that the player can enable once they're used to what do the buttons do, and don't need a highlight for deletion.