Congrats! I adore my boa. Personally I wouldn't worry too much about the attitude. He's been through a lot of is probably still settling in. I would double check your temps just in case. Too much heat can make them cranky.

My boa hates moving. He's been moved twice in the past year and let me know he was NOT happy about it. He would hiss whenever I opened the door and he's big enough now he gets his way usually. Now that I have been in my current home for a couple months he has settled in and is back to being his easy going self. He's such a sweetie now and I have no trouble with him. I have found they calm down as they get bigger, though he was never much trouble as a baby.