Here is the Spartite website link that contains a FAQ section. Spartite is poured with the rigging loose, but the rig positioned by lines tied around the mast and winched to make sure it is centered and proper fore-aft location. The backstay should be on tight when Spartite is poured.

You line the hole with Vaseline on the mast and deck so the Spartite "donut" will slide when you pull the mast. It usually stays with the mast.