You can set the window size of the project in the (project settings) area on the left side in the editor.
But in order to see that specific screen, you first need to click on your project folder on the right side of the screen.
So click on the right in the project window on the top folder.
Then you see on the left side a change in the editor.
It now says Project settings.
There u can set your window size.
The window size is different from the layout size.
This way u can see a small or large (user defined) part of a layout.
To make the layout itself larger, you just click in the gray area in the editor, and then the (project settings) window changes into the layout properties window.
If however in the future u want a small (view) window in your game and a big layout.
Then scrolling is the answer.
Thought this was wat u were searching for.
U can add links to your posts and replies.
So people can have direct acces to your (in dropbox) uploaded Capx.