Sounds like and from looking at a couple of photos of your trailer you may have the Schwintek slide out system which is what I have on our bedroom slide which is electric. Our two lower level opposing slides are hydraulic.
If your slides are the Schwintek system there are a few things that you can try to get things back in sync. One of the more important things to remember on the Schwintek system is that after you retract or extend the slide do not release the button right away. You should hold it for an additional 5 to 6 seconds to allow the control memory to record the slide position.
Take a look on the track and see if any signs of the teeth of the rail showing any shaving of material which could indicate that the slide out was not installed square.
Take a look at this link, it's a group of videos posted by Forest River they offer a wealth of information.
Videos by Forest River RV
As for the battery issue, if your trailer does not have a battery disconnect you can pick up a simple blade type at your local Walmart, auto parts store or even on Amazon. It's as easy as removing your negative battery cable, clamp the disconnect in place and then clamp the battery cable on the disconnect.
Good Luck and Happy Camping