I'm 90% certain that this method is being used as the copy protection:
******************************
How to make activation keys:
1 - Upload a .txt file to a host. This must have a static url, or it wont work.
2 - Once someone gets a key by any means you want, be it purchasing or asking nicely, add that key to the .txt file.
3 - Key is compared to the ones in the server by a simple python script, could be something like this:
Code:
key = renpy.input("Key: ")
import urllib2
python:
try:
for line in urllib2.urlopen('key database site'):
if key in line:
activated = 1
except:
activated = 0
4 - Send an email to you from the client. This is also python code (dont know if its included with ren'py, you might have to get the module from a real python installation).
Code:
python:
email_message = "Key "+key+" has been redeemed."
import smtplib
server = smtplib.SMTP('localhost')
# This line is configured like this: server.sendmail('from', 'to', 'message')
server.sendmail('your client email acc', 'your email acc', email_variable)
server.quit()
5 - Edit the .txt file and remove the key so it can't be redeemed again. You can also place a button in the client that once the key has been activated requests a new key. That would ask for the person's email and use it as the 'your client email ' to send the message to you. You send them a new key if you find their email on a list which you should keep and send them their key again. Once you send the key be sure to add it to the .txt file so it can be redeemed once more.
There are a variety of ways in which this code can be modified to fit your needs. And like all my codes, credit is appreciated but not necessary. Also, you might want to run a renpy.full_restart() after the code is run, so as to clear the url data and avoid bugs while saving/loading.
*********************
I only know a little C programming but what can be done is to recompile an exe which basically circumvents that copy check and since the full game is there it shouldn't take too much work for a person who knows what he/she is doing.