I'm a little disappointed with the complexity, but ok, commendable and the first version
I THINK THAT AXYZ SHOULD UPGRADE MOVE from sketchup and not behave differently!
1st selection - without clicking, but in the case of two objects on the floor, when selecting from one object to another, the floor is also selected - unusable in most situations
2. the first step is to determine the position of the gizmo? Let it appear immediately in the center at the bottom and you can already start selecting on the gizmo, and if you click somewhere else, the gizmo will move anyway.
3. Snap doesn't work, and we're all used to it being on all the time? Turn it on and it works by default according to sketchup, you can also set the option to turn it off by pressing a key (for example ALT)
4. When, say MOVE, when I click to mark the arrow, the base point should be in the center of the gizmo and not at the place where I grabbed the arrow.
5... if the creator is interested in more detail... because there is potential