Don't worry.
It should be pretty straightforward if you use as a template a current script that implements EverythingInterface (e.g. this one).
Here's a script that adds the following columns:
Newest File Date CreatedOldest File Date CreatedNewest File CreatedOldest File CreatedNewest File Date Created (Rec)Oldest File Date Created (Rec)Newest File Created (Rec)Oldest File Created (Rec)Newest File Date ModifiedOldest File Date ModifiedNewest File ModifiedOldest File ModifiedNewest File Date Modified (Rec)Oldest File Date Modified (Rec)Newest File Modified (Rec)Oldest File Modified (Rec)
Newest-Oldest v1.0.opusscriptinstall (2.3 KB)
Note that I barely tested this 
, so you'll be the official tester now.
It should be very fast (depending on your Everything config, of course, but it's designed with speed in mind), both for recursive and non-recursive columns.
I tested with Everything v1.5 on my machine. The script is very basic, so it assumes you already have Everything properly configured (created/modified properties indexed, etc.).
It's designed to reuse the data as much as possible, so it doesn't query Everything for each column. Sometimes this can work against it, (I think it's some quirks with multi-column behavior).
Currently subfolders are ignored when picking the data. You can change that in the code if you want, by editing the Everything query.
As for filenames related columns, it currently shows the full path. Edit as needed.
Let me know how it goes (maybe this one deserves its own thread here 
?).