I understand the frustration. If you read my "stove story" at the bottom, you'll see that it took me 10 years to "just get the stove to burn", and even now, I don't know why the issue has turned around 180*
Also, you'll note, the heat transfer issue didn't cure it self with the wave a wand.
It seems like it's time to re-group! You know what doesn't work ... yet, but you don't know "why". I have one off the cuff thought, which is, remove the duct from the register or whatever near the stove. Allow that hole to be open between the basement and stove (for a test) .. see what happens. My thoughts here, .. bring combustion air up from the basement area. The air coming out of the bedroom grate has me confused, as to where it's going and why. Also, with a "closed duct-work", where is it coming from?