Clicking the house icon will close the current project and return you to the home screen.
Clicking the save icon will save the current project.
Clicking this icon (Hotkey '1') will activate the select tool. You can use this in the viewport to select the node you want to manipulate.
Clicking this icon (Hotkey '2') will allow you to change the position of the selected node along the X, Y, and Z-axis.
Clicking this icon (Hotkey '3') will allow you to change the rotation of the selected node along the X, Y, and Z-axis.
Global Space mode means that any changes you make to the position or rotation of the selected node will also affect the position of the child nodes further down the chain.
Local Space mode allows you to manipulate the position and rotation of a node without it affecting any of the child nodes further down the chain of the hierarchy.
Flip X, Y, Z
Using each of these tools (X - Red Arrows, Y - Green Arrows, Z - Blue Arrows) will flip the entire rig and models to a mirrored position along the correlating axis.
Inverse Kinematics (IK)
This tool turns on the Inverse Kinematics (IK) controls. This means that instead of the parent influencing the child further down the chain (Forward Kinematics or FK) a child down the hierarchy influences the position and rotation of the parents it's attached to.
This is useful when animating something like a hand, where the forearm, upper arm and shoulder follow the position of the hand, rather than controlling the position of the hand by animating the shoulder.
Align to Axis
This tool will automatically align the rig to the closest axis at a right angle.
Show/ Hide Rig
This tool will show or hide the underlying rig (Skeleton) that shows the connections from one node to another.
Show/ Hide Bounding Box
Every model attached to a node will have an underlying bounding box, defined by the overall size of the model file. This tool allows you to turn the visibility of the bounding box on and off.
It is possible for a bounding box to be bigger than the model if the underlying file hasn't been cropped to the voxels.
If the VXM model file attached to the node has any emissive voxels (ones that 'shine') this will toggle them on and off in the display port.
This tool will reset the display port by centre the camera on X-0, Y-0, Z-0.