Are these layouts responsive?
Yes. They mostly are. They obviously best viewed on desktops (1920x1080), but also mobile friendly.
Do they contain any advertisements for your site?
There will be only a short credit text to my site on the footer. Other than that, no.
Are files packed in a ZIP?
No. They all are in one HTML file. Otherwise, it would be very painful to debug and update them in the future.
Do they contain any hotlinks?
They only contain hotlinks to my site. They're usally images or fonts. Layouts sometimes get updates. For this reason, I recommend you to download the external files, otherwise it might've get broke in the future.
Are they suitable on any browser and OS?
I guess so. I usually make them based on Google Chrome and Windows OS.
Can I use them commercially?
No. They are only made for indie, educational or personal sites.