CF8 without Aux button?

Can a Crystal Focus 8 be wired without an Auxiliary button? Reading the manual I see it is mentioned frequently not only as a way to cycle menus but also in diagrams. I did not plan for one when I was designing my hilt. I am almost done with my hilt and just realized I might "need" to have one to make the CF8 work. I do plan to have a RICE port and frankly that was how I planned to control the CF8.

Anyone know whether that will work, or do I need to just break down and find somewhere to stick an aux switch?

You'll likely need to find out how to fit an aux switch in. Without it, you lose a lot of functionality.

The biggest issue you'll face is not being able to trigger the blade lockup effects as well as blaster blocking effects. A lot of the advanced functionality you'll lose includes menu usage, selecting sound banks, color profiles, etc. You're correct that you can do those actions through RICE, but that means you'll always need a computer handy. The board will handle a lot of what you'd use RICE for (except for color blending if you're doing that).