Issues with downsizing items

Try using the square bracket keys. They are the ones that normally make things bigger or smaller, at least on PC. I don't know if MAC is different but I don't see any reason it should be.

[ to downsize items. 
] to upsize items.

Still having trouble?
If so, please explain in more detail what your issue is.
From what I've read in your post, it sounds like you can make it bigger, so it should work. So I'm guessing the issue is something other than it not working. For example, if you make the window smaller, it leaves a hole of the original size.
Once we know the details, we'll be able to explain in more detail how to deal with it.

Thanks Regard.