Smoke detector issues

I am working on a home cinema room, and have been doing pretty much everything on my own. I have soffits surrounding the room, and a closet in one corner where all of the low voltage and speaker wiring will run. I live in a state where no permit is required for low voltage, so I didn't really give this much thought when I was purchasing everything to do this, but now I am having second thoughts, and want to make sure what I have done is not some sort of code violation or something. The soffits I have built are framed in 2x4's, with sheetrock on the bottom, and removable wood panels covered in fabric all along the face. There is fiberglass insulation inside of the soffits to help reduce echoing inside, and I have constructed foam boxes that separate the insulation from the lighting fixtures by roughly 3 inches. I'm not really sure if this particular build for soffits would be classified as "in-wall", but I want to be certain. I am using a 12V system for my lighting. I have a 350W power supply in the closet, which powers a 24 channel DMX dimmer, with 3A per channel. From the dimmer, I have a few 20awg, 2 line red and black wires fed straight through the closet wall, and into the soffits, which are fed throughout the soffits to each lighting fixture inside of the boxes. The fixtures are cheap LED downlight fixtures with LED drivers attached. The wires are wired to the drivers inside of the foam boxes. Additionally, I have several 20awg, 4 line "rgb+" wires coming from the dimmer, also fed through a hole in the wall, into the soffits, and around the room to feed a series of RGB LED strip lights for accent lighting down the columns, and across the riser. My questions I guess are, is this setup problematic? If so, what would I need to do in order to make it non-problematic? Thanks!

I have an electrician that was supposed to be here to replace my old breaker box with a new, larger one. Haven't heard from him all week. While waiting for the electrician, I have proceeded with other work, including running a new line for the refrigerator. I have a 220 outlet directly below the breaker box. It is powered by 2 connected breakers with a 30 amp label. I want remove the outlet, and use one branch to power my new fridge receptacle. Im sure it isn't good practice, but is it safe?