It is possible to activate a full-version on a PC not connected to the internet using the "offline activation" system built into PC TuneUp Maestro.  You will need to use a second system that is connected to the internet to make this happen, in addition to the non-internet PC.  Here is what you need to do:

Install the trial version of PC TuneUp Maestro to the non-internet PC

Then, starting with the non-internet connected computer, open PC TuneUp Maestro
Click Register Now
Enter the license number 
Click Activate Now
An error message will appear with a URL in it (Http://...), save the link to a text file

Save the file to a memory key (or some means to take it to a computer connected to the internet)
Send the file to us at:

support@compuclever.com

We will then create a file and send it to you with instructions on how to use it to register the program on the non-internet PC