I don't think it's unreasonable to think that someone who has installed software before would have perhaps missed a standard disclaimer of possible damage. A lot of people don't read anything while installing software unless it says "next" or "done".
The OP was asking a valid question -- is there a non-developer version of decal. The answer is no, the version available at decaldev.org is the only verson availabe at this time. That is the version that everyone is using.
Tadoshi, if you want an idea of what others have gone though before you decide if decal is right for you in it's current state, I suggest you poke through some of the issues people are currently having. Most people are having good luck getting it to work but it does depend on your ability to follow very specific instructions. You can find that information and more in the user to user forum (and read the sticky).
http://forums.acdev.org/phpBB2/viewforum.php?f=14