The upgrade itself doesn't do anything. The unit you want to be affected needs a trigger for the upgrade, in the form of an xxxUpgrade module. All xxxUpgrade modules (for a list, see module guide *points at signature*) constantly look if a certain upgrade is activated. If it is, it applies a change. But the same upgrade can do different things for different units. You could just as easily upgrade the Command Center's hit points with Advanced Training, but at the same time give Paladins a better weapon with it

. So I advise you to look at the module guide *points again*, it doesn't contain ZH modules yet but I'll get into that soon.