Per our corporate and industry standards, the positive Z axis points up. (We use start models that have changed the default view and annotation planes, so "Top" view shows expected orientation, rather than out-of-the-box creo default orientations.)
When using "Shaded with Reflection" Shade style, in order for the reflection to appear in the expected ground plane, it is necessary to go into the options and change the setting in the "walls" pop-up menu. This change must be made every time a new model is loaded, as it is not saved. We would like to save this option permanently, for all models and all users.
The setting is found in Options / Model Display / Real-time rendering settings / Walls. Default is "XZ plane (-Y)". At our site, we would like it to stay at "XY plane (+Z)".