Unzip the contents of "GameData" to your GameData folder, same as with most mods.
I've always liked the planet info display in the planetarium (in the tracking station, or in map view during flight). However, it's never felt quite right to me-- it's missing some bits of information that I find important, while "wasting" valuable screen real estate for some parameters that don't really have any practical in-game use.
This mod addresses that.
Here's what it does to the planet information displayed:
(See forum thread for FAQ regarding any questions.)
The default behavior is tweaked to be the way that I, personally, like it, since it's my mod.
However, I realize that not everyone necessarily has the same preferences I do, so you can tweak it as you like via the game settings dialog.
Default settings are shown above. Note that if you like showing the planet's area, mass, and gravitational parameter (as the stock game does), you can turn them on.
But wait, there's more!
You can also customize the colors used for the text, as well as the numeric formats used for showing the information.
You can do this via a configuration file, PlanetInfoPlus.cfg, which you will find in the mod's folder.
Raw stats are from the beginning of time until now. Each follower and download entry represents one hour of data. Uneventful hours are omitted.