First of all, I fixed my puzzle 47 (Tapa Mosaic) yesterday. It solves fine now. My sincerest apologies to anyone who tried that and got the uniqueness issue.
Coming to today’s puzzle, I’ve always wanted to construct a marathon puzzle ever since I saw this. Just to be sure I got it done, I chose Akari for the first time. I’ve triple checked this, and I’m quite sure it works fine, but still, I’ve uploaded the solution too today itself, so you can check in case you go wrong.