Symantec WINDOWS INSTALLER EDITOR 8.0 Reference page 98

Windows Installer Editor Reference
Installation Type). During a Custom installation, the end user can turn features on
or off individually.
Each installation has an installation level, stored in the property INSTALLLEVEL.
Each feature has its own installation level value, which is set by this field. If a
feature's level is less than or equal to the installation's INSTALLLEVEL property, then
the feature is installed. By default, INSTALLLEVEL is set to 3 for a Typical
installation, and to 1000 for a Complete installation.
Normal
Set the feature's level value to 3, which means that it gets installed by default
for either Typical or Complete.
Never install this feature
Set the feature's level value to 0, which means that it won't appear during
installation, and won't be installed.
Always install this feature
Set the feature's level value to 1, which means that it gets installed by default
for either Typical or Complete.
Custom
Set the feature's installation level value yourself. Example: if you want a feature
to be installed for a Complete installation, but not for a Typical installation, set a
custom level value that's greater than 3 and less than or equal to 1000. The
Custom Value field becomes available.
Custom Value
If Custom is selected in Level above, enter the level value for the feature in this
field. For details, read the description of Level, above.
Note
The end user's action on the Installation Type dialog box determines the
INSTALLLEVEL property. To see how this works, go to Setup Editor > Dialogs tab
and click the Installation Type dialog in the list. Double-click the Typical/Complete/
Custom radio button, and you see that the end user's choice in this radio group sets
the property InstallMode. If you then double-click Next on the Installation Type
dialog box and view the Events tab, you see that, based on the InstallMode value,
the installation property INSTALLLEVEL is set to either 3 or 1000.
Display
Specify if and how the feature is displayed to the end user on the Select Feature
dialog box during installation.
Invisible
Do not display the feature.
Visible and Expanded
Display the feature and its children.
Visible and Collapsed
Display the feature but not its children.
To expand or collapse a selected feature's children, display hidden features, or
display the features' titles rather than the features' names, use the right-click menu
on the Features page.
See Features Page on page 91.
Defining an Installation Project
98