I've seen a few different ways done, magnets, elastic and Velcro, but really you wouldn't be able to fit much in them, I made my TD with removable ends but to date have never used it.
Grappling hook/box and comlink is not a problem as they are an option for a hero version, so is the different hand plates.
Other differences are green bubble lenses, three ear bumps, 2 ear screws, only three teeth, holster has four mount points.
As I mentioned to your GML you do need to send in reference material (photos/info) with a new to the legion costume.
Guidelines for submitting new to the legion costumes is here: http://www.501st.com/databank/Costuming:CharacterApproval
Seems the LMO has deemed the costume to need a finished CRL before anyone can be approved.
There are guidelines for new character approval to the 501st: http://www.501st.com/databank/Costuming:CharacterApproval
I am not sure about the legalities of the NDA from Anovos
When you aren't in a rush there's more time to look over a problem and ponder solutions, not just rush to one conclusion .
Looking forward to the rest of the build.
Hello and welcome aboard, as you say AP is available now and there is a wait for the Anovos. Also AP armor we now is approvable, the same can not be said about Anovos at this stage as nobody has seen as yet
Good luck what ever you decide, lots of helpful people here to guide you on your journey
Hello and welcome aboard, I waited from 1977 until 2012 until I could get my first set of armor, take comfort in knowing there will be supplies available when you can afford it