The reason for the tempature is not the adhesive. It is for the concrete slab and the VCT itself. If you install warm VCT on a cold slab, the VCT will shrink and you will have gaps in all of your seams. If you install cold VCT on a warm slab you won't have much of a problem, but there is the possibility of some of the tiles edges starting to peak. (from expanding from the warm slab, cold tiles).
The VCT actually has a chemical reaction with the adhesive over a 72 hour period, where as the tile backing actually melts to the adhesive.
You can easily replace damaged tile's without the use of a machine. Simply heat the tile with a heatsource (propane torch, heat gun, etc.) and the tile will peel right out. As the heat reactivates the adhesive and you can slap in a new tile and it will stick like new. If you have a coat of wax on the floor, make sure to take a utility knife and score along the seams of the tile you are replacing. Or when you go to peel up the tile you are replacing. The wax will pull up and chip the edge of the surrounding tiles.
I hope this helps. I do have 23 years experience in commercial flooring and have laid well over a million sq ft of VCT over the years (grocery stores, Target's, Wal Marts, Fred Meyer's etc)
