Protecting mah program

- I have written a program, I want people to pay for it
- It is a type of program I don't expect hackers to have motivation to hack (it's a recipe program)
- If the program doesn't receive a valid activation key, it goes into limited trial mode
- The activation key is the SHA1 hash of the installation key + a guid I picked.  They must enter this key to get out of trial mode.
- The installation key is the SHA1 hash of the hard drive model + serial number.  They get this and must email it to me with money.
- I don't expect typical users of this program to know how to spoof the HD serial number (lol females).
- Did I do this right?  Suggestions?

- If the program doesn't receive a valid activation key, it goes into limited trial mode
Just make it think the activation key is valid.

/profit.