To answer your question, NO, you don't need gold in the license tests. You just need bronze. You need gold in all sim and arcade mode races (hard level for arcade), and on all time trials.
Welcom to GTP mate, nope golds aren't required for 100% (thankfully ) as neon and meekeal said. I can't get golds on IA or S, although i think it might be due for another go...say in one more year.