Lovemythermo - You have probably looked it up now but guar gum just helps to "combine" the ingredients like the gluten in wheat flour would.
You could easily substitute the GF Plain Flour for normal Plain Flour, use normal baking powder and leave out the guar gum if you wanted "normal" fruit bread.
Miss 4 was so excited this morning. Her appetite has been a bit hit and miss the last few days but she quickly polished off a slice toasted with some butter and then had another slice in her lunch box. She announced at breakfast that it was "delicious" and something about me being the best mummy in the whole wide world .... shucks!