You might want to try ClickTeam's
Install Creator
Here is a quote about the Professional Version...
Quote: "A version specially designed for professional use, and especially for people who write shareware and make register-able demo versions. Its basically the same interface, with the possibility of having several versions of the software in the installer, for example one version for unregistered users, and one version for registered users, with the possibility to protect a version with registration codes and other nice features. See complete feature list below."
I used the freeware version in my first FPSC release, but I didn't need any registration codes.
The FREE version can be used for commercial purposes, which is nice.
Quote: "A complete version of Install Creator with unlimited rights to produce installers for both commercial and non commercial products. "
So, this is a real handy tool for FPSC users.