InstallAware

I am brand new to using InstallAware, I just installed the evaluation version yesterday. I am using a .NET setup project. One of the requirements of my installation is to run an executable to install a printer from a 3rd party. I have this working correctly for install, and it runs the executable with a different command-line for uninstall correctly as well.

What I cant get to work is having it remove the printer during an upgrade. I think the upgrade logic is working because I see a message about removing files when using the installer after having installed a previous version, but my executable isn't running. I put the entries in the Pre-requisites section on line 27 of the .NET template and also tried around line 47 of the same template. I know the "Run Program" statements are correct because I cut/paste them from the uninstall section, but they never execute. Any ideas?

Edit: I enabled every dialog box and now when I launch one of the "Requirements" is showing as "Remove Previous Installation". When I click past it I think it is removing it because my desktop shortcut id deleted. My custom executable is never run though.

I've continued to work on the problem and have an interim solution that raises another question.

The reason the actions would not run is in the MSIcode the $TARGETDIR$ and COMMONFILES properties are not set until after the section of code that handles the upgrade. I moved them up and it is running now.

The question that raises is this.. If I want to run a custom action from the installed directory during an upgrade, how do I know what the $TARGETDIR$ is? I know what it is if I remove the dialog box that allowed the user to change it.. but lets assume that during the first install the user installed to a different directory than the default. Is there a variable that represents the previous installations directory?