Some design changes to the custom properties.

The custom properties are wasting too much space with those separators, you can almost get double the space by removing them without losing any thing( readability,UX..etc).

My suggestion is to allow for users to add the separators by themselves through the custom properties option, this way we gain more space and have some sort of grouping but not only that selecting and changing bunch of them at once becomes much more easier than with the current design and please allow for double column layout like it used to be.