ALLUSERS being ignored; can't get a per-user installation

[Minollo]

My installation needs to be *always* per-user.
I removed use of ISSetAllUsers; I don't show the CustomerInformation dialog; in Property Manager I've set ALLUSERS to an empty string (I've also tried removing it from property manager, no change).

But when I test the installer, I always end up with the uninstallation information in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall instead of HKEY_CURRENT_USER.
Why? What am I doing (or not doing) wrong?

Thanks!

[TsungH]

If you have not, please refer to ALLUSERS property. You will also want to verify value of ALLUSERS property in installation log.

[Minollo]

Thanks for the quick response.
As mentioned, I am aware of the role ALLUSERS is supposed to have; I'm setting it to "" (or even removing it from property manager).
I have run a verbose log, and I found no mention at all about ALLUSERS...