I've not been on the CampInn user forum for a couple months and just saw your posted question about towing with an Element. Sorry for the delayed response...
Regarding opening the tailgate or rear hatch with the TD hitched, I've not had any issues. The tailgate just clears the tongue clamp lever on the trailer - but just barely. Ball - hitch height will have some bearing on this...
I bought a device that clamps the ball mount to the hitch receiver - this eliminates slack and therefore the clunk of the ball hitch in the receiver every time you start or come to a stop. Available @ Amazon
http://www.amazon.com/Hitch-Clamp-Heavy-...y+duty+-+2+inch
Overall the Element handles our 550 SUV with little fuss.
Keep in mind that my Element is the SC model which has a lowered suspension (about 1-inch lower than LX or EX models). Pay attention to the height of the hitch ball. I had to find a ball mount with about a 2-inch rise to be within the recommended hitch height. Different height ball mounts are available to accommodate the recommended tongue height when hitched. See the towing basics section / page 37 of the CI owner's manual.
If I were to do it over again, I would not purchase the SC model for the reasons below. I suggest going with an EX or LX model Element. Regarding a 4WD model, I've gotten along fine with the front drive SC - but then I"m very selective where I tow - no trips up a single lane dirt forest road.... 4WD will also drop your MPG by a mile or two.
1 - The larger wheel size on the SC means more expensive tires when time to replace.
2 - The larger tires have less sidewall which along with the SC's lowered suspension, makes for a stiffer ride. The SC certainly handles corners better with the lower suspension and larger diameter tires, but the trade off in ride comfort isn't worth it in my opinion.
3 - At 65,000+ miles, it's time for new shocks / struts. The SC's lowered suspension requires a special strut for the front wheels which is only available from Honda which means they're more expensive. The rear shocks are the same for SC and non-SC models and there are non-Honda parts available at lower cost.
On the plus side, the Element is a box that has tons of volume behind the front seats which is great for stowing camping gear. It's not aerodynamic but I still see an average MPG in the low 20's while towing.
Last fall I was towing the TD north on I-25 between Albuquerque and Santa Fe, NM. It's a steady climb up to SF and we had a really stiff headwind. To keep a decent speed the transmission frequently downshifted to 4th and 3rd gear. Honda engines typically hit their peak HP and torque at higher RPM's. The engine is designed to handle the higher RPM's and has to work harder in these situations - but it does handle it if you're willing to drive a little slower. Towing is a slower drive anyway so it doesn't bother me.
Finally, if you get an Element with an automatic transmission, I recommend having the transmission serviced more often. I also use full synthetic engine oil (Castrol or Mobile 1).
Let me know if you have any other questions...
Eric