I did swap a new derailleur:
Shimano Deore M615 Shadow Plus Rear Der
as well as a new 10-speed shifter and 10-speed chain. When trying to size the chain, it would either be too tight for the large cogs or too slack for the small ones. I tried a couple of different lengths in the process and probably need to get a new chain now because some of the chainlinks are a bit tight now from the adding/removing of links - but that is a seperate problem.
As fat as the BB30 bottom bracket, I was not planning to purchase the one in the link, I am able to get almost new cranks (exact same model) with a different bottom bracket for $50 - hence the interest in using them. Attached is a pic of it: