For Aligment properties, when you adjust the drop downs menus to “Fill” for either Horizontal or Vertical and the corresponding Width or Height size properties contain values, nothing happens. I would expect it override the Width or Height paramters and remove the attribute from the UX file. A simple fix would be to disable the corresponding size parameter if “Fill” is selected.
To visually reinforce this, you should rearrange the order of Vertical and Horizontal Alignment drop downs to better associate Horizontal to Width and Vertical to Height. I would also encourage you to set the width of the Width and Height text inputs to the same width as the drop downs as well as align them to each other to further associate their relationship.
In Sublime, you should remove the associated Width or Height attribute from the UX file when “Fill” is selected.
To reproduce this, create a Dock Panel. Use the inspector to adjust the width. Then adjust the horizontal alignment to “Full”. Notice nothing happens. Also notice deleting the width property doesn’t fix it. You need to physically delete the attribute from the UX file. Instead it should immediate clear and/or disable the associated Size property from the inspector input as well as clean up the UX file by removing the associated attribute.