I created my first installation setup with InstallAware and used the StrataFrameMergeModule.msm to install my application.

Now I have an update ready to be send to the customer, but the SF libraries has been updated several times but with the same version number. 

How do I make sure my update will replace the SF libraries in the Windows\Assembly folder at my customer with the latest release used to build the update?

Also, are the SF libraries build into the StrataFrameMergeModule.msm or just a reference to what I have in my developer computer?

Thanks!

Correct.

No, it will look in the GAC first then the root path.  So you will want to remove those entries from the GAC on the machines you have already installed your application.  But once they are removed, the assembly will look within the path to find any other assembly MicroFour or otherwise that will not be in the GAC.

Sorry to ask this, but what would be the proper way to remove those file from GAC?  I don't see any command in IA to do it.

Also, since the version number does not change with un-officlal updates from SF, I believe I would need to force a delete of those files, before installing/copying new ones with IA, because I got the feeling IA will just compare the file version and not the datetime stamp in those .dll files.

This was what I was referring to in a previous post about writing a .NET program that is call through your IA install to do this for you by calling the gacutil EXE.  We use this approach to get around the shortcomings of IA including a full system check to make sure that the machine is up to specs before allowing the install to move forward etc.

In the EXE that we create we will set the exit code and then test on the IA side if the exit code was a legal value ( you can decide what is legal). 

In .NET, you can exit an application with an Exit Code which will allow any program that is calling that program to determine if the run was successful or not.

To exit with a code other than 0 call the Application.Exit(YourExitCodeValue).

They will, but should really never be a factor as your program should uninstall the previous version before loading the new version.  If you do not use the MSM, IA will remove the assemblies from disk when it is uninstalled....and you could call the program you create to remove any references from the GAC as well.