Setting up a project
Adding PowerUI to a project is as simple as dropping in the package then delete the example scenes folder. No further setup is necessary aside from running it at least once (so it can automatically setup itself).
Creating the Main UI
GameObject menu > UI > PowerUI > Main UI
This will create a GameObject called main-ui in your scene (feel free to rename it). If you click on this GameObject, you'll see that it has a manager component on there.
Creating a HTML file
Either just create a .html and drop it in, or use a helper UI:
Create > HTML file
Applying the HTML file
Click on main-ui and then the PowerUI Manager component to be able to select the Html file for it:
Note that the manager component is designed to be changed.
We're really devoted to providing you as much help as we can. If anything doesn't make sense or you need more guidance please don't hesitate to get in touch!