An old installer script I have inherited has the following peculiar behaviour I’d like to clean up:

1. set WIXUI_EXITDIALOGOPTIONALCHECKBOXTEXT to enable the always-present checkbox on the Finish control
2. publish on Dialog='ExitDialog' Control='Finish' a CustomAction conditional on WIXUI_EXITDIALOGOPTIONALCHECKBOX = 1 AND NOT INSTALLED that generates a PDF in a temporary folder and displays it once

Now, I’d have liked to change this behaviour to one a bit more reasonable:

1. (as previously)
2. call the CustomAction always, in-sequence, Before='InstallFinalize' to put that PDF directly into the installation folder, where it can stay instead of being functionally lost after one use
3. display the PDF conditional on WIXUI_EXITDIALOGOPTIONALCHECKBOX
4. remove the PDF on deinstallation

Am I right in thinking that I cannot actually use the WIXUI_EXITDIALOGOPTIONALCHECKBOX for that?

My understanding is, that in order to (be allowed to) write into the installation directory, I must Execute='deferred', for that I must order it Before='InstallFinalize' and this means it is run before the user sees the checkbox.

Do I really need a manually created extra dialog with a manually placed extra checkbox, both requiring magic numbers for their non-optional X and Y attributes, instead of using the checkbox that is automagically placed correctly onto the dialog that itself is automagically always present?

Currently the PDF generator also does the displaying. Can I create a different Publish element that only displays the file? (Reading from installation directory should be fine out-of-sequence, right?)

(In case you wonder, why: The installed application has a button to display the generated PDF – and currently the generator is bundled with the application to generate it again , instead of displaying the perfectly good original lost to some temporary folder. If I can put the original with the installed files, I can have the application display the original and strip the generator code from it, decoupling these concerns. I fell over it, because – as such things are bound to happen – the application-generated PDF had a wrong date filled in. Can’t happen with a Single Source of Truth(TM). Of course I’d like to not add another dialog to the installer, as nothing was added – I am taking away!)