Just joined. In need of consulting, would be extremely grateful!!

Hi community. So I've been a BMW owner for over a decade. From the first time I sat in one I haven't owned anything else. I've been thru two 3 series and now own the 645 e63. I've had the car for around 4 years and over that time I have taught myself a lot in regards to diagnostics, troubleshoot and repairs ranging from mechanical to electrical to software operating with Inpa and Ista. My current issue stems from replacing the eccentric shaft sensor as well as some gaskets and o rings while I had the valve cover removed. After repair and reconnecting my battery I've had a load of trouble that has culminated in no crank no start. I would be so grateful to get proper consulting from a knowledgeable source so that I could go over what issues I've experienced, what steps I've taken to troubleshoot and where to go from here. Any help would be F-ing awesome. CHEERS!!!