When making a tileset, you can set the size (also when making a scene), so make sure those are 32x32. If you want, you can always visit my livestream for faster help (livestream.com/stencyl).
If you want to, another way of doing it is to keep moving to slide 32. That one is about the scene creation tool; in the upper-left, you can switch to actors and manually place the player on the screen that way. It can be simpler than doing it via math and code.
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You're welcome (and welcome to the livestream ;) ).