|Think about Loose Coupling|
Some time ago, when Strawberry was nothing more that a sweet idea, and ActivePerl was the only Perl available for Windows (not counting cygwin), I took a version of ActivePerl, which, at that time, still used perl to install itself. I modified the installation routine to run without prompting, and stuffed it all into a self-extracting ZIP archive. I also bundled some packages, like DBD::ODBC and DBD::Oracle, and of course the application itself, and installed them after having set up perl, all from within the installation script.
Yes, that looks ugly and was ugly, but still better than a manual installation.
Today, I would use Strawberry Perl, the application itself, and perhaps a small part of CPAN, bundled in an InnoSetup package.
BTW: You and your customer might think that there is no Perl installed. But when you install Oracle, you also install Perl. Unfortunately, that is often a very old Perl, and it is really hard to get rid of it. (Sure, you can simply delete it, but a clean uninstall also removes many other parts of Oracle. Explain the customer why you need to delete parts of Oracle.)
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)