Welcome and good luck!
Always wear gloves and a respirator ...and get a good digital thermometer!

And here's the answers to you first 5 questions!

1. Why are my baits sticky and/or Cloudy? Temperature ...you must get the plastic to 350F to fully change state. Make sure you stir it!
2. Why did my plastic turn yellow? Temperature....you got it too hot.
3. Why are my baits not filling all the way? Temperature...you need hot plastic to flow well into the little cavities without setting up prematurely and blocking the fill.
4. Why are my baits denting: Temperature...your plastic is too hot for a big bodied bait and it's sucking in the skin that has already set and is the weakest area.
As a general rule: Heat your plastic to 350- and pour at 350 to 320.
5. Why are my baits to soft...sticky....bubbles
..? Make sure you mix your plastic WELL...EVERY time you use it.
Have fun!
Andy