The same Template you will use to insert the dwg drawing to, just remember to save as a .tcw when work in TC and then save back to dwg if you need that later.
Or you can make Blocks in a drawing and using x-ref to that Block when insert to the drawing
Or make the object's and drag them over to the Library palette, then they will be easy to Access from whatever drawing, Block is good if you should have many of the same object's in a big drawing, think filesize.
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