It would be awesome if an instruction file was included with the program.
So far, there are no instructions anywhere to be found. I did fine without instructions but not everyone will have such as easy time installing without some guidance.
At this point we don't have any sufficient documentation for this.
As a general theme guidance:
1) Copy an existing theme to a different folder
2) Change theme.xml accordingly. Make sure you change "key" node.
3) Open Admin Area -> Appearance -> Choose Theme page. It will list the new theme which you can activate. Let me know if this works for you.
With plugins it's much more complicated and I suggest you to wait for the official manual of adding a plugin.
I like that shadowinc.iooffers more than just a basic search for people. They dig into public records from top-notch sources like corporate directories and government agencies. It's the perfect way to find out who owns real estate, where a person used to live, or even get detailed business information.