The path should look something like this:
Zombie's Retreat - Beta 0.9.3\www\save
Select everything in that file and copy it after installing new version. Then paste them in the save data folder of the new game and delete the old version of the game.
Sorry for taking so long to respond. From what I know you should have gotten the ability to make the Heating element from Leslie. She should have given you something like a book that automatically adds the recipe. I'm not saying you did, but I missed the recipe several times at first in my crafting bench cause I kept reading over it. If you haven't got the event where she gave you the crafting book, again it automatically adds the recipe so you don't need to read it, then you need to talk to her either during the morning or midday, can't remember which to get it.
Really loving the game. Shied away from it for a bit since I wanted to wait till it got a little further along in development. Doesn't scratch all my itches, but it's good quality. Story isn't entirely unbelievable Well, except for unlocking the glory hole on the very first day you can roam.
However, I seem to have found a bug. The water collector doesn't work.