There don't appear to be any rules regarding going into bear form while already wild shaped, so it's probably best if you just went with a reasonable interpretation. Reasonable, for me at least, would be that the latest effect is the one that takes over and replaces the other. So the bear form would take over from a wild shape. You do have the option to do a regular rage and not go into bear form though, and the rage would work while wild shaped.
Raging technically doesn't prevent the character from using SLAs or supernatural abilities, so you could probably use wild shape while raging/in bear form, but it's probably best if you lose the bear form. I'd probably rule that you could keep your original rage bonuses though
See what your DM has to say though.
Girallon's Blessing does work on creatures that don't have "arms," so it seems reasonable that it could indeed work while wild shaped. While in bear form is a different matter since you can't cast spells while in a rage or bear form, so you'd have to cast the spell first. Letting the spell continue to work if you decided to wild shape or go into bear form is a difficult one to answer. Enough so that it's probably better up to the DM to make the call.
Based on how the 5th level features work, one idea is that you'd only gain the appropriate one for each of your uses. For example, you could use your Changeling ability as a move action, but you couldn't do the multimorph ability with Minor Change Shape since it doesn't qualify. Your Polymorph spells would qualify for multimorph though, so you could change your shape during a Polymorph as often as you wanted so long as it wasn't your original form, but you couldn't use it as a move action.
