Sorry, my last post on this did not show up.
for the most efficient heights for Esbit. The range is 1.25 to 2.25. After that, efficiency drops rapidly. Note, that the height is from the top of the tablet. It will burn down. Also, wind really effects Esbit. Even if you have a good windscreen, I find that the lower height gets more heat on the pot.
If you cut a regular soup can to leave 3 or 4 colums just short of 1.75" high and a 1/4" rim of can around the base, then fold the top corners in to make triangles all the way to the base, you will have a pretty good pot support. Add a windscreen and you will be in business.