Hi @lee1,
Welcome to ZapWorks! 
So, @stivalar is definitely right for the second question - we have a Target Manipulator subsymbol you should be able to use. You can find it in the ZapWorks Studio software and also on our documentation site here.
As far as adding a reset placement button - I’d definitely consider checking out the Controllers and States documentation, as I have created a quick example using the Instant Tracking subsymbol to show you how this behaviour could be achieved.
Instant_Tracking_Reset_Placement.zpp (1.0 MB)
The only difference to the original symbol is that I have created a Reset Placement UI
Group node which includes a replacement button. In the Normal State
script, I use the code:
symbol.nodes.Replace_Icon.on("pointerdown", (e) => {
symbol.controllers.states.elements.Placement_Preview.activate();
});
To go back to the Placement Preview
state once the appropriate icon has been tapped.
Hopefully this helps!
Have a great day!
Francesca 