Why is LuLu now poopin in the corners on carpet?

I am a new member & hope that I am doing this correctly. I am inquiring as to whether anyone has any advice for me. I have 5 indoor cats and my last addition is approximately 8-9 months old now. I have had her since she was approximately 4 months old. She was a stray kitten that I brought home from the neighborhood. She immediately began to use the litter box and approximately 1 month ago, she started using the corners of my living room as her preferred pooping preference. I have never had this problem before. I have encountered my kitties peeing in the wrong places, but never pooping on the carpet. I am now putting down layers & layers of newspapers on a daily basis & have scolded her the couple of times I have been lucky enough to catch her at it. I do not want to put a litter box in my living room due to the odor problems plus I am afraid my other 4 will take this as an invitation to use the corners rather than their litter boxes. Also, I have noticed that she and my Rascal (my 2 year old female) do not get along anymore. Rascal stays in the bedroom and watches LuLu like a hawk. LuLu seems to be the instigator from what I can tell and she and Rascal have tied up on occassion. This is has never happened before either between these two. Any suggestions on how to rememdy this and why she started this behavior to begin with? FYI: I had her spayed 2 weeks ago and this has not helped as of yet.

Is Rascal the alpha cat? Lulu may be challenging her for the position.
As for the pooping, layers of newspapers won't make her stop. You have to really clean the soiled area with specific products to remove the odor and traces of poop.
If it is really not possible put the litterbox in the living room, can you just ban Lulu from going there?

You know, I cannot really tell if Rascal is the alpha cat. She is really the more docile of the five and not very social. I do not think that she is b/c she is really pretty submissive to the other 4. Rascal's sister is the most social of the five and wants to be wherever my boyfriend or myself is. Lulu is actually the most dominant and I am just beginning to notice that as she matures (being still less than a year old).

I realize that the newspaper will not make her quit. I just had to put it down to protect the carpet until I can figure out what to do. I think maybe she does not like to use the litter box b/c it is in the back room with only way in and out. Rascal usually stays in the back room or in the bedroom (through which you must go to get to the back room). Could it be that she is avoiding confrontation with Rascal by avoiding the two main rooms that Rascal typically occupies? I think I am going to try and move the litter box to another room and see how that works. What do you think?

Thanks for your interest.
fantangrasdalulu