You're having problems with the extended battery door pushing the battery against your screen? Wow, that's very odd. Mine seems to fit just a tad bit loose if anything. I've considered pushing the stock door onto it just to see if I could tell if it was pushing against the screen or not, but I haven't had any problems with cases fitting around the extended battery door at this time. Oh wait, I think it just dawned on me what you were saying... did you mean with this case on it puts pressure on the extended battery door? That would make sense. And to that I would say absolutely you should be fine taking the battery door off and everything being alright. At the very worst if/when you drop it the battery
may come loose on you. But hey, that's better than a damaged X right?