Denis-

>InstallShield Express will let me install everything needed by my app. After I have installed my app am I forced to install upgrades still with InstallSHield or will I be able to install those manually.
>
>In short can I replace only some files with a couple of new ones. Like the exe, some metadata tables... manually instead of having to install those by uninstalling the app. (Forced because of the use of ISE) and then install again my app.

Yes. You can just xCopy whatever you want.

>To me to be forced to uninstall and then re-install does'nt make sense but I'd like someone to clarify this issue.

If you want to install from a Setup again, if you're using the FoxPro Lite version of IS that comes with VFP, you have to uninstall first. Being able to update requires you upgrade your version of IS. Worth it, I found.