Congratulations!
In terms of first steps I'd echo the "dive it stock" comment as overall it really works rather well (I dive dry so the wing isn't an issue) and in general it's not a unit you have to tear apart for general maintenance/cleaning so there's no excuse for changing something whilst it is apart.
In addition to the changes to the webbing (uncrossing) I also purchased a tool for unscrewing the plate on the canister (photos on Rebreather World somewhere) and bought a "constrictor" oil filter remover (see
Amazon.com: Westward 5PV89 14-Inch & 4-Inch Boa Constrictor Strap Wrench Combo Pack: Home Improvement ) for an example.
I use this on the occasions that cold hands mean I can't unscrew the loop.
(I am certain that the Boris was designed with apes in mind).
As a non-VR3 user I found the handset a bit of a learning curve - but the usual rule applies RTFM! I did generate some paperwork to help me learn about the Boris handset operation (it isn't identical with the VR3) so PM me if you'd like a copy.