Thumb icons going green is the symptom of the Missing Sims issue.
Of course, they are there, the game just lost the references to them and cannot call the proper image belonging to the Sim and some of the Sim data. Which is why the thumbnail image is gone.

Oh well I guess that would be considered Missing Sims. It's a shame it happens though because to me WA is a good game, I like exploring and such.

It is related to WA though, I played some families for quite some time lately without going on any trips, all still there (Although since getting Awesomemod more bugs are rising, I don't think I unistalled the Config package when I went to change some details about it on the online one,. might change to Twallan though). I am going to attempt to do what the Wiki suggests, always save and have a backup. It's the only thing to do, that's if I can be bothered playing Sims 3 again lol, I am taking a break from it for now, all these bugs and stuff really got to me.