The separation between the text and button is relative to the width of the column. There is no setting to change it in the module, but you can reduce the column the module is in and that should be the best way around it.
The border colors only apply when you set the Button style to transparent. Once you do, it takes the background color as the border color.
Is it possible to change the border color of the button by css? How? I want to have solid color in the button background and when hovering white background with border in color, and I cant with the element options.
To add a border on hover, you will first want to set the hover background color. Then go to the Advanced tab on the Call to Action module and in the Class option field add my-hover-btn. Save the changes and then add the following to your custom CSS: