The brace will cause a shadow if the light is directly overhead. The closer to the brace the light is, the bigger the shadow. You can't move the light around in the Aqualight Pro so the only other option (short of getting a new tank or light unit) is to remove the brace.
I wouldn't do that personally and it will void your tank's warranty. However, there have been a fair number of other people who have removed their support braces according to the postings I've seen on various reef boards.