When you zoom in our out in these applications the focus or center of the zooming is not the object in focus but the position of the mouse pointer

Yes. That's the expected behavior.

lace a cooker in the corner, it will nicely snap to the walls but when you place a fridge next to the cooker, the fridge will snap to the horizontal wall but it won't snap to the cooker, you can slide it left and right, it will never snap. It looks like an object will snap to a wall won't snap to another object.

That's where you use the align tool. As I mentioned; the magnetism only works on walls and heights: snapping objects to a wall, or placing them correctly on an elevated plane, such as a table. Using the "side by side"-option in the align tool, is the best solution. Shortcut: shift+cmd+b on OSX, so probably shift+ctrl+b on windows. Fast and simple.

cec