In Free Transform mode, hold down the Shift key to maintain a mathematical relationship (eg, when re-sizing, shift will keep the length and width relative to each other, when rotating it will rotate in 15-degree increments, etc).

Glad you're learning! I've been using Photoshop for so long that I consider it very intuitive, and have a hard time understanding Corel's programs.

They had chained him down to things that are, and had then explained the workings of those things till mystery had gone out of the world....And when he had failed to find [wonder and mystery] in things whose laws are known and measurable, they told him he lacked imagination, and was immature because he preferred dream-illusions to the illusions of our physical creation.
      -- HP Lovecraft, The Silver Key