In Creo Elements/Direct Modeling it is possible to use the tab key to change the context when selecting items between only the objects that are completely within the box and objects that are completely or partially within the box.
In Creo Elements/Direct 3D Access the tab key does not have this functionality.
As 3D Access is generally used by persons with a limited command of the program, it is not acceptable to expect them to change the context in the settings menu before performing the selection (and then resetting it again afterwards!).
The tab key should receive the same functionality that it has in Modeling.