I’m relatively inexperienced with Zbrush and I would appreciate any pointers you have. I need to pose some models, but the problem I have is that the joints, or parts that would normally be deformed, are covered in a lot of hard surfaces, which I have as individual subtools. This hard surfaces will look bad if they deform, so I’ve been posing the model and then moving each subtool into it’s proper place, which is very time consuming. Is there an easier way to do this? I’ve used Subtool Master, but I need the deforming model underneath to “carry” the hard surfaces intact and not deform them. I’ve searched the interwebs, but I haven’t been able to find any short cut. I would love to hear how wrong I am! 
The transpose master plugin will fuse all the subtools into a single one so you can pose everything.
… one thing that might help to achieve your goal: when using the transpose master, each subtool becomes a polygroup (activate polyframe to see the polygroups) - which makes it easy to select one or more subtools while masking the other subtools/groups
keep in mind that while in transform mode, ctrl-clicking a group will unmask this polygroup while masking the other polygroups, a handy way to “isolate” polygroups in terms of masking
But there’s no way to have ZBrush understand that some subtools are meant to escape deformation during posing, right?
I’d love to be able to assign certain subtools as “non-deformable” but still keep some kind of relative position when I pose the entire model.
If not, man, that’d be the plugin of my dreams.