We've approached this in 2 ways here:
1. When uploading the installer package to the catalogue, also include the files to be copied post-install along with a script that basically calls the installer, and then copies the files to the destination afterwards e.g.
msiexec /i installer.msi /qn
copy filetobecopied.txt c:\destinationfolder
Use that script as your commandline in the package resource. The downside with that is you have to create your own software detection rules etc.
2. Create a separate task that copies the files (copy file task), and include that task as a post-install task in the managed software delivery policy or in a job that calls the quick deploy task for the software installer first.
Hope that helps.