extract email address

Why are some result order greyed out?

First, you should understand why there is a list of with numbers, to sort with.

Some sort orders could produce an equality between items, like company name. Other cannot: alphabetically for instance will take the whole word and sort things alphabetically, meaning there can not be a sort equality between two items.
Any sort order placed after alphabetically will not be used, thus greyed out.

The same happens for original text order