Hi @photodave ! 🙂
That is a very good question!
Indeed, all of your render nodes will need the .maxtool in their paths to be used by them.
The workflow is not yet super ironed out, but here is a few things you can do.
Like you mentioned, you can manually copy the tool to all the render nodes in the "user folder" that "should" work, given you know what user is ran when max is started on the render nodes.
You could also copy it to the Max system (program files) folder, that would also work.
Both are a little tedious to do though, specially if you want to add tools often.
Max will pick up automatically all tools in these folders and in this order (if a tool exists in two locations, the first one will be used)
There is also a way to specify custom folders, this is what I would suggest for render node.
In order, Max will build tools from :
. Max system folder.
. User folder.
. Custom folder.
To add custom folders for MCG ,in 3ds Max ini file add [key] and value as follow (path1 is a string that can be anything as long as it is unique) :
[MCG Compound Directories]
path1=D:\some\local\path
path2=\\some\network\path
(add as many paths a you need)
[MCG Tools Directories]
path1=D:\some\local\path
path2=\\some\network\path
(add as many paths a you need)
All render nodes 3dsmax.ini will need to be edited to add the paths. Once this is done, they will pick it up from all renders.
For instance, you update 3dsmax.ini to point to Compounds and Tools on a Network path.
You can copy (or edit from directly if you set your local Max ini to have the same network path) any tools / compounds in those paths and Max will pick them up on start up.
This is a summary of the network deployment guide :
http://area.autodesk.com/learning/3ds-max-mcg-network-deployment-guide
Let me know if you need more information! 🙂
[edit] :
You can also bake animation on a Max transform controller to send to rendering, to avoid MCG dependencies, if that can ease.