First of all, please accept my apologies for the delayed reply (I was off last week due to not feeling so well).
When we upgrade the installer, files get copied to the destination folder again.
That kind of implementation I want on the Maintainance VerifyReadyDLg Install button.
Please note that an upgrade basically consists of two processes:
- the uninstall process of the older version
- the install process of the newer version
This is the reason why the files get copied to the destination folder again.
If you want to deliver a new version of your file, then the best approach would be to go for an upgrade.
The "Maintenance" mode is used post-installation, if the user wants to add, for instance, a feature that he did not add during the first-time install (as explained in the "Maintenance Installation"
What you want to achieve may be possible through a Custom Action as I have previously mentioned. For instance, you can have a custom action that downloads the new files and replace the already existing files.
However, I believe it would be better to just go with an upgrade installation, since this is the purpose of it.