Yes, they will soften in the heat. I do not recall reading about anyone adding gumtex, but it would be interesting to find out.
Theresa 
My dd made me some for a cake in March.....they did not get soft. Customer said that they tasted good though! Katie was really good at doing the roses.......I did not try. She wanted to learn how...so I said have at it! 
She made my roses the day before........they were not rock hard, just really firm. HTH. 
I didn't add anything to mine. You could use them the same day you make them, they don't need to dry out or anything like that, or you could save them in a ziploc bag and use them later. Don't store them in the fridge, they get runny from the condensation as they warm up.
I've made both Tootsie Roll roses and Starburst roses several times now. (I'm new to decorating, and for some reason I just can't get those darn bc roses right!) I didn't use any petal shaping tool (the first time I did it I had no idea there even was such a thing! lol). I just started by forming about 2/3 of a TR into a tear-drop shape. After that I broke each TR into 2 or 3 pieces and just used my fingers to form rose petal shapes. By the time you get them formed into petals they are a little sticky from the heat, so you can just wrap them onto your rose base and they stick on their own. I just keep making petals and sticking them on until my rose is the size I want. I'm not sure if I explained that right. Oh, and I put the bag of TR's under my knee while I was making my roses. That way they're already warmed a little bit by the time you start working with them. I have several pics of TR and SB roses in my photos. Feel free to pm me if you have any questions.
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