Some folks in these forums recommend Silaprene, Sikaflex or Dicor. My experience is only with 3M 4200 and 3 M 5200.
Here is a link to a comparative discussion (I'm sure there are others):
http://www.popupportal.com/threads/dicor-sikaflex-or-3m-which-do-you-love-and-why.99499/
also a link to a discussion in these forums:
http://www.wanderthewest.com/forum/topic/13368-roof-leak/
and another on the Expedition portal:
http://forum.expeditionportal.com/threads/112832-Adhesives!!-need-some-help-Sikaflex-vs-3M-vs
My guess is several or even most of these would work for your application.
Good luck,
Craig
Edit: In case it is not obvious, none of these sealants are intended to provide "structural" support and are mainly intended to seal against leaks. Fasteners having good engagement with a frame member are needed to actually hold the latches (and similar items with a load on them) in place.
As with any coating, epoxy or sealant, proper surface preparation in accordance with manufacturers directions is essential in order to achieve a strong bond with the surface(s). In particular, Aluminum develops a thin oxide layer rather quickly and that layer typically needs to be removed before painting or bonding in order to get good adhesion. Scrubbing with a cleanser like Alconox (basically Ajax without aromatic or chlorinated hydrocarbon) does a good job of removing the oxide layer. I'm sure Ajax or Comet will work fine too. However, in all cases sure to rinse well with clean water and then blow it dry or let it dry well before applying the sealant, epoxy or whatever. .
For reference I have done a significant amount of bonding and painting of Aerospace assemblies which were subsequently tested for appropriate adhesion. I have seen a lot of the qualification test results as well. There can easily be a difference in the adhesive strength of 2x, 3x and more between a properly prepared surface and one that has not been properly prepared (or poorly prepared). Yeah, I know we are not doing Aerospace work but if we want the these things to hold up over time the same chemistry and Physics apply. ;-)