All PixelPacks include original .psd files where each sprite is on it's own named layer. In each PixelPack there's a playable scene that showcases the use of most of the included elements (sprites and animations). Majority of the sprites are tilable and/or can be flipped. Base tile size is 16x16 pixels, but there are also larger (or smaller) sprites included, that may use some other square power of two (e.g. 8x8 or 32x48). PixelPacks also share the same 16 color palette (except for the PixelPack Forest, that uses 256 color palette).
Project is created with Unity 2019.1.8f1 to ensure backward compatibility. Compatibility is also tested with Unity 2019.2.x, 2019.3.x, 2019.4.x and 2020.1.x (however example's platformer code is provided as is without any warranties, PixelPacks are graphics packages and provided example is just additional content).
If you're working with latest Unity versions, you may need to update 2D Pixel Perfect package from Package Manager to version 2.x (or later). This should happen automatically, but sometimes Unity fails to do this. Prefabs/sprites in demo scenes have Layers and Sorting Layers specific for this project. If you are using them in your existing project remember to change them to conform to your Tags and Layers settings (or replace ProjectSettings/TagManager.asset with the one provided with this project. Warning! It replaces all layers and tags in your current project). If you just want the sprites, create a new temporary project for this asset and then export/import only Sprites folder to your project.
Example code utilizes free third-party libraries UniRx (licence) and DOTween (licence) that may or may not have issues with the Unity version you are using. Ensure that you have compatible version of both libraries installed (in later Unity versions: see Package Manager).
If you encounter any compile errors after importing the package, open the Package Manager window and ensure that you have installed packages that are compatible with the Unity version that you are using (e.g. 11.10.2020 the latest released 2D Pixel Perfect package version was 3.0.2 but the latest Unity 2019.1.8f1 compatible 2D Pixel Perfect packge version is 1.01 (preview)):
Example code is fully documented and commented. You can find the full code documentation/reference from here.