Tried making gel-type candy, it recrystalized as it cooled? I wasn't sure if it would work anyway, but I always used to love the tubes of squeeze candy you could get when I was a kid. I tried to make it by modifying a hard candy recipe. I boiled it for about ten minutes at about 220 degeees F. 

I removed it from the heat, mixed in my flavoring, and it was pretty much the desired texture when it started cooling. I put it in a container on the counter overnight and it seems to have just returned to the state of its base ingredients? I'm not sure why this happened, or how to prevent it in the future. Any advice?
Try using sugars that even in concentrated and cold form do not crystallize much - like honey, industrially or home made invert syrup, thick jam...