Building time settings only happen if you set a Build Time greater than 0 in the SelectObjectBtn.
This takes in a canvas element, that will display while the object is being built. It could be one of the provided TimerCanvas prefabs or something different entirely that you wish to display while it is being built.
This material is applied only to the temporary timed object. Once the object is built, the temp object is destroyed, and the actual object with its original material is applied.
You can also choose to leave this blank and just build with the original material.
Set the Timer Canvas to appear a set amount in meters above the objects height. The objects height is calculated from its collider.