Installation
Install the mud via NMM is easy: Just activate it.
For a manual installation copy the two files AMatterOfTime.esp and AMatterOfTime.bsa to your Data directory (usually located at C:Program Files (x86)SteamSteamAppscommonskyrimData).

Uninstall
If you want to uninstall the mod using NMM: deactivate it.
For manual uninstall delete the two files AMatterOfTime.esp and AMatterOfTime.bsa from the Data directory.
Uninstalling the mod should not effect anything within the game.