Installation issue on Vista RC1 that is not seen in XP or 2k

I have a device driver installation package using the deployment method for
creating the MSI in Visual Studio 2005. This MSI places all of the files on
the PC needed for device driver installation and then performs a custom
action to call an executable to pre-install the INFs and drivers onto the PC.
For Windows XP and 2k this mechanism works fine. But when I installed the
MSI on Vista RC1 or earlier I always received the message
"There is a problem with this Windows Installer package. A program required
for the installation could not be run. Contact your support personal"
which forced the package to unload. Before clicking the OK button I check
the directory structure and everything is present and installed in the
correct directory.

I tried using the msiexec command line option to log the installation but
the package was not installed correctly. In the MSI we create and install
the INFs and drivers in the

C:\Program Files\Common Files\Motorola Shared\MotPCSDrivers.

When I run the command line option the installer installs the files in

C:\Program Files\Common Files\Motorola Shared\MotPCSDrivers\Common
Files\Motorola Shared\MotPCSDrivers

which is completely wrong. The installation completes but the installation
did not add my menu items in the start up menu or does not show up in the
add/remove programs for me to uninstall the MSI.