The BMW break up of Rover was messy, and I suspect deliberately so. They separated Land Rover and the Rover Group engineering function off and sold the lot to Ford for more than they paid for the entire Rover Group 6 or 7 years earlier.
They kept part of the Rover Powertrain back, and sold it to MG Rover at a later date. They also kept the Swindon Body and Pressings plant, the new MINI (largely engineered by Rover engineers), the Cowley manufacturing plant, and a raft of heritage brands (such as Triumph etc), as well as the Rover marque, which was only licensed to MG Rover, (apparently at Ford's request) so that they could not use it to create any sort of 4x4 vehicle that might have been confused with/or harm the Land Rover brand.
They also retained the rights to the new medium size car which would have replaced the Rover 45, leaving MG Rover without a crucial new model.
Hence why MGR had to focus on the MG brand. When MGR collapsed (which was probably always inevitable, given that BMW had left that part of the company unsustainable in the long term), BMW made even more cash out of the whole debacle, by then selling the Rover brand to Land Rover (Ford), to prevent anyone else from using it.
That denied SAIC/Nanjing, who bought up the carcass of MGR, the chance to buy and use the Rover brand themselves, so they they created the Roewe brand, which is pronounced similarly, and has a badge that is very similar to the original Rover badge!!!
MG Rover had sold the Longbridge site and leased it back, and the writing was on the wall. Didn't something similar happen with Trollhatten??