Most RGB strips are 10mm wide, they will fit in the Rails, just has to be fed from one end. If its more than 10mm then its a no go. It could be a few things but I think heat is one for sure. I had that issue when I started with ABS, everyone said high temps and no cooling, turned out that I needed cooling . Also if you missed a layer it was most likely a small jam caused by heat creep. I would try a lower temp, maybe 180C as a base. Then maybe check the part cooling fan and set higher.