This might be something really obvious to someone who knows better but i've never really played in a college house for any length of time before, and also not with the version of the game I have.
So for the last couple days I've been playing some sims through college, and sometime at the start of sophomore year (they are both currently in semester 1 of sophomore year) I started getting this weird behaivor in my game.

Whenever any sim tries to use the toilet or bathroom (both for showering and to clean them in the case of the maid) they do the action for 'i can;t get there! something is in my way!' and then show that image in their thought bubble. They can usually get into the bathroom if i removed the shower (previously it was the schmidt's wunder tub. Now it is the cleanwater shower system with a recolor)

These are the areas of the house I know are effected, and the 2nd floor which I have not seen effected. I recently rearranged the bathroom and still got that error. The only way i can seem to get around it in the bathroom is to take the shower out of the bathroom, wait for the sim to be finished, and then replace it. I have noticed this behaviour with all 3 sims that are in there regularly (my 2 playable sims and the maid) but I don't know if other sims such as houseguests have done it.
I am using the UC on Win 7. I have a few mods in my game, all listed here:

- apartments and shopping on the same lot, from MogHughson
- use inaccesible beds from simological
- a mod that allows me to try for baby with same gender couples and one that makes joined unions marriages from twojeffs on simbology

I am also using 4 cc objects in the home: the showers on the 2nd floor, the laptop on the 2nd floor, the plant on the desk, and the desk itself.
AFAIK none of those mods should interfere with routing or whatever else is going on but i wanted to list them anyway just in case.
If i left out anything important just ask and i should be able to get the info.
Thank you for your time!

First, you need to get the essential mods that prevent game corruption. They are listed here: http://modthesims.info/showthread.php?t=532696

I use the UC as well, the problem is not with the game version; the game is buggy and the essential mods are essential.

The bathroom looks usable to me. But it seems that there is something there, even though it is not visible. To solve this, I would start by moving them out, refurnish the empty lot and move them back in again. Or just move them to another lot - because, sometimes, a lot is just buggy.

The lines in the Sim''s thought bubble also seems weird to me, although I am not sure what causes it and how it can be corrected. Maybe somebody else can help here.

You do need the esential Mods, but there is another Mod that can be very helpful.

The stuckobjremover Mod, it is available on MATY. Just place the object-box and then it will eliminate invisible items etc. for you. What i suggest is that you get the stuckobjremover.package and then place it in buy mode all over the area where there is a routing problem. The stuckobjremover Mod will remove any invisible items if they are there.

Get it here http://www.moreawesomethanyou.com/s...2.html#msg54122

I actually do have that mod, thought it was also essential

Batbox would do it too.

Not sure if this has been said, but my guess would be you have some invisible objects in the way, usually invisible kicky bags. The bat box should take care of them but if not try placing down the stuck object remover, also a pescado mod, it looks like a yellow box and it will detonate anything..

Yeah, that's definitely tiles that are improperly marked as occupied. Removing the shower presumably fixes it because it opens up space for the sims to go around (though looking at the arrangement, I can't see how that works). This is not peculiar to college houses but can happen anywhere. I once had a tile with a stuck "jump rope" action.

The lines in the bubble are what you get when the game doesn't have an icon for the problem and just puts up all of them squished together.

Thank you to everyone, i'm going to try the stuckobjectremover first and go from there!

Edit: It worked, it deleted a hidden object in both areas.