I've used Satin Ice for years, and just do not have all the problems that others report.
1. You do have to knead it until it warms up and becomes elastic. The kneading activates the gums in the product that make it elastic. Probably 5 minutes of kneading.
2. I always roll it out with the thinnest film of veg shortening smeared on the counter. Haven't used a mat, just because I was taught to pick it up supported by my forearms and place it on the cake.
3. Fondant goes on a cold cake better.
4. The temp of your cake has nothing to do with making bubbles under the fondant.
5. Cakes don't make gas.
6. There is, quite naturally, air inside you cake. It may be between the filling and the cake layers (see thread on "My newest trick" to get air out of cakes and prevent bulging) ; it may be between the bc/ganache and fondant. To allow it to escape, you *always* run a thin sharp knife edge along the bottom of the fondant and board. Sealing up the cake too tightly by thoroughly pressing the fondant to the board traps the air underneath the fondant. As it naturally tries to move out, you'll get a bubble. If the tier is to be stacked, just poke a hole (skewer sized generally works) into the top. This hole will be covered by the next tier.
7. If you do get a bubble, insert the tiniest straw like thing you have into the bubble and suck the air out. You are not putting your mouth on to the cake and you are not blowing onto it. Suck the air out. To repair the hole you just made, dissolve some of the fondant into water and make a thick, thick paste. Using a light touch and a small spatula or knife edge, repair the hole with the paste.
8. To keep your fondant softer, after its applied, rub some veg shortening - a tiny bit - onto your hands and rub your hands lightly al over the cake. It will be a bit shiny, but the fondant will stay a bit softer. However, applying dusts will likely be streaky if you're applying them all over, and painting on the fondant will likely not be successful. If you're just applying fondant decos, there's no problem.
9. Fondant is *supposed* to get firm on the outside of the cake., Very firm. Some people might call it hard. It's what it's designed to do. It seals the cake. If you don't like the product, use bc.