Over the last years I have written a voxel editor called VoxelShop in my free time. Features are still being added, but there is already a lot you can do!
The animation option sounds very interesting (not having worked with VoxelShop). If you would support the formats used in relation to Stonehearth, i.e. .qb from Qubicle Constructor, .json for Skeletons and Animations, this could be quite interesting.
In addition… it is a free tool at the moment, right? Any plans for paid editions?
Releasing the source code is something I was thinking about already. There are some pros and cons though. What I do have is a fail-save already. So if something happens to me the project will go open source.
And I will create a video once the animation part is fully implemented. Until then you’ll have to wait.
Btw: If you’re worried about “installing”. This doesn’t install anything on your OS. It will just sit in it’s folder and you can delete that and all is gone.