Well, I can see why there's an antiMacheist group on Twitter. Obviously, there is no such thing as customer support from MacHeist. What a waste of my money....
Have you emailed support or contacted a moderator for help? There is plenty of support available, you just have to ask for it. Mike (handling email support) and I (forum support) answer every message we receive.
Regarding the questions as to why it tells you there are 15 days remaining, etc....almost all demo programs are like this. They will show a countdown until you enter your license information from the menu bar across the top of the app. Click --> "purchase-->unlock Espresso".
To gift the app to someone else, send the dev an email with your name and license info, and include the name and email of the person to whom you are gifting the app.
For those asking about customer service alternatives, the page for Espresso's very own customer support can be found right here.
You've just read my signature