I purchased UG Powder from Global Sugar Art and I am not sure exactly how to use it. Can I add it to Fondant or Gum Paste if I am making flowers in order to make them stronger? If so how much do you have to add?

No, it's not an additive. It's piped on its own after mixing with water.

From the Global Sugar Arts website:

Clear Unbreakable Gel by Orchard Products. Mix with water, let stand 4 hours then pipe exquisite lace or filigree that will harden and be virtually unbreakable. Orchard Books 14 & 14 give detailed instructions and ideas for the gel. 20g. The gel can be colored. (5 mls= 1 tsp.)

From Almond Art.com
This wonderful invention comes from Australia. Simply add hot water to the powder (can be coloured with food colouring) and stand until cool. Can be piped into 'edible wires' or lace work, bells, flower stems & ornaments. Can be dusted with powder colours when dry.

HTH
Rae

Just one question - is this similar to Sugar Veil? If not, how does it differ from piping with royal icing that hardens?