Yep, I meant for herb that I plan on immediately taking out of storage, grinding, and loading into an ELB.I also have this case, not hardly as elegant as my larger Nanuk but then again a tenth of the cost. Has the foam cut-outs, too. Perfect for the beach.
"Recommended dryness for EVO ELB's?" - Presumably you mean only your herb.
When I first started vaping, I purchased a humidor with the accessories. Spend a fair amount of time figuring it all out. Sorry to say, IME at least this was unnecessary. It can even be counter-productive, i.e., it's possible to over-moisturize and even create mildew, so getting the technique down is important. Now the box holds my small vaping pieces and looks nice on a bookshelf. But no herb.
I now use an airtight and light protected coffee container for about an ounce, and an airtight jarz for small amounts. For longer storage, a mason jar covered with aluminum foil in the freezer.
I'm going to experiment, but I think what I'll do starting out is use the Cvault and Humidipak for all long and medium term storage, then remove it a day or 2 in advance before grinding and vaping. I tend to keep weed for a while and tend to have issues with it getting very dry, so I like the idea of maintaining its moisture level.