As a very skilled cabinetmaker I would need to see pictures to see the extent of the damage.
As an expat of B.C (Saltspring Island) myself, I do have experience with B.C's weather; while the interior can experience high levels of heat and humidity the coast tends to be cooler and less humid, unless raining.
I'm not 100% familiar with AS cabinet door construction but I'm having a little trouble believing the interior panels swelled up to break the miters, as most interior panels fabricated today are a veneer over an inert substrate, such as MDF or a type of Luan; only direct exposure to moisture (sitting in water) will swell them up. Also Hickory along with Beech and White Oak are an extremely tough wood that doesn't allow for as much water absorption, which also has the downfall of not as much glue contact in the miters; but AS should have used Dominoes or hardwood biscuits?
I'm inclined to believe that the cracking is due to DEHUMIDIFICATION, ie the wood dried out due to your extensive use of dehumidifiers; see link below. The humidity in the trailer should have been at say 10%-15% to maintain the moisture content in the wood.
They live just above you in Comox, (so does my sister).
http://www.airforums.com/forums/f44/...ed-146543.html
Send me pictures or post them and I'll try and find out all I can about AS door manufacturing.
Cheers
Tony