So I built my Lakeview Manor Home and furnished it with odds and ends, a housecarl and Lucia, the orphan from Whiterun. I was making some nails outside when my follower - Amanda from the Girls of Skyrim Mod - asked me, unprompted, to be my steward. Perhaps, mistakenly, I agreed. As my steward, I can ask her to follow me again, and she will, but as Steward, I can not fire her and look for a new steward, I don't have that option.

The reason I want to get rid of her as Steward is that weird things started to happen around the Manor after she became steward. We took off for some adventuring, to raise some capital to buy more house supplies. Upon our return, I was working inside the Manor to build new items and heading back outside to create new iron fittings and the like. This one time, as I stepped outside, I heard bandits. My housecarl and my follower started running around the house. I did too. I could hear them, but could see no one. Then, as I watched the red markers on the compass, it appeared that the bandits were inside the wall of the manor. A quick TCL verified this, as I saw two of them between the geometry of the house. I went back to normal mode, saved, exited and reloaded. Poof, no more bandits, it seemed.

I though that was the end of it. But then, as steward, I asked Amanda to purchase a horse, which she did. I took the horse into Falkreath to purchase some more lumber and iron, leaving Amanda, the steward, at the Manor. Upon my return, she bolted toward me and my mount and attacked and killed my horse. $1000 gold down the drain in just under 3 hours of game time, 5 minutes of real time.

Even that wasn't the end. Later, inside the home, i started to hear some weird banging, that wasn't me hammering away on the construction tables. I followed the noise and found Amanda as a Steward, having it out with my open trophy room door. I had made her steward once again so she could fill my animal pen with chickens. She kept attacking the door over and over saying stuff like, "and you thought I was just a pretty face." I could not get her to stop. I could not talk to her. Eventually, I timed it just right and clicked on her immediately after using the RESETAI console command (evp did not work). I made her my follower again and tried to get her out of the house, but she was still on alert and would not follow me. After a few reloads, I was able to get her outside, where i saved and quit and came here to ask WTF?

I mean really, wtf can I do? Do I have to abandon the Lakeside Manor? Should I kill Amanda - who is a GREAT follower, or should I just forgo the pleasure of having a steward?

Sounds like it's because you made her steward more than a bug related to Lakeview Manor as I have never encountered problems with it like you have. If you have an earlier save reload and say no when she asks. Make your housecarl and see if a vanilla follower has the same problems.

No save available. I am well passed the time of reloading from before I made her steward as we have done quite a few quests since then. I am contemplating killing her and getting a new follower. But she is a good follower and I don't know if I will get the option to hire a new steward if I kill her, though I can always reload if not. I guess I'll try that out.

Likely the only bug was the house ate the bandits, which can happen to anyone, on the Xbox 360 I lost the children for a few months in game time after Lakeview Manor gobbled them up. I have since restarted, did not trust that house, the wife used to just walk out through the wall.

I would not have made an NPC added by a mod a Steward just in case, you could have always said no and chosen someone else. Being Steward is a life time position, the only way to fire them is to kill them. Normally you could hire another Steward, not sure how that would go with a character added by a mod, but you can always just save it before you try it. You should always save your game before making such important decisions, in case you do not like the outcome.

Personally I would just go on a hunt to check if you had any two legged vermin in the walls, or under the house.

This.
Just make Rayya (the Housecarl) Steward.
Let her follow you first, so you can smith up her scimitars and bow and give her enchanted rings/amulet...

You could also try dismissing her as a follower, then saving the game, disabling the mod, finding another steward for the house, then re-enabling the mod.

Yeah, I regret ever letting her become steward. It just caught me off guard, and then we left for hours of questing before I noticed any weirdness. Live and learn, I suppose. I am going to TCL my way around the house, both interior and exterior, just to see. Good advice.

I could kill her, but she is set as essential, so I'd have to look up her base form ID in order to make her killable. It's probably just easier to try out what JosieJ said.

I'm gonna try this right away. Though, whenever I dismiss her as a follower, she resorts to being a steward, so I'll have to do this far enough from the Manor that she doesn't go on a rampage again.

Just out of curiosity, what is the standard way of getting a steward? Is it a new dialogue option you get with perspective applicants? Or do NPCs come up to you and ask for the job?

Its a new dialogue option and sometimes followers will approach you about it as well.

I think I have resolved the issue, bit I'll have to wait and see. In the end, I had to lookup Amanda's Form ID and remove her essential flag so I could kill her. Just removing her mod did not allow for the Steward dialogue to return. But after killer her, not only was I able to hire a vanilla steward, Amanda also sent me a 300 GP inheritance, even though I was the one who killed her!

Anyway. I saved, removed her mod, reloaded again, saved & exited again, added her mod back and reloaded one more time, then found her and made her my follower once again. So, it looks as though everything is copasetic once again. Only time will tell if more weirdness will occur, but at least my new steward didn't kill the chicken I sent her out to get.