Hi Isabel.
Try armadillo from
www.siliconrealms.com . You'll need to professional version in order to compress VFP executables.
It is an advanced copy protection system, you can use time limitations, number of starts limitations, usage of license keys, hardware locker, protection again clock forward, clock backward protection. Encryption. It also can compress your executable. In my case it shrunk my 9MB into a 2MB executable, which increases loading it from the network.
It has many more neat functions in there you might find usefull.
If you'd ask me the $250 for the professional version is well worth the cost, but of course you can try before you buy.
Walter,