Back to LV6 there was a bug in windows that made the executables creation date wrong. It couldn't be fixed before the file was wrapped in the installer. I fixed that by replacing the VI in the Application Builder that invoked the Installer creation VI. The replacement VI did correct the creation time of the exec before calling the original VI.
The AB has changed much since then. If you dare to look into the AB hierchy of VIs, maybe you could figure which VI invokes the Installer and make the needed modifications of the exec there. You can do this by creating a Wrapper VI. Rename the VI you want to replace and create a new VI with the same name and connector pane. Your VI will therefore be called by the AB. When called, modify your exec and invoke the original VI. Alternatively, you can also try to figure which VI in wininstall.llb is called by the AB and wrap it with your own VI.
I think the OpenG Builder hasn't yet an installer but it is coming soon.
