If you'd like to give it another try, I've uploaded some screenshots to explain how to change the house's "size" (more like the house's scale). That's probably what's holding you back, it turned out very confusing without a tutorial... Basically you need to click on the tabs on the catalog where you can choose the furniture: it changes the house's scale and you have to match the animal's size.
Anyway, thank you for playing our game despite the technical difficulties!