Ok, let's see if I can explain it better.
In the saves tab, the colour of the save (on the left list) is actually more important. The list on the right relates to that.
If the save is a purple check box, then the list on the right should all be blue check boxes. Blue text are esm's, black text are esp's. And everything is perfect.
Of course, we're not in a perfect (gaming) world.
If the save is a blue check box, then you're still good. It just indicates there are some mods in the list that are not used in that particular save game. Usually seen when using profiles and different mod lists.
If the save is a green check box, it's still good, but not perfectly in sync with the current mod list. You may see in the list on the right some green boxes (like in your picture). All this means is that those mods were installed after that save game. No check means it's not active. If you want, you can right click on that save and select Load Masters to load all those mods into the save game. Really not necessary though. If you were to load that save and re-save it would come in sync anyway.
If the save is an orange check box, it's still good and just means that your mod order has changed since that save game, such as having removed a mod and re-ordered with BOSS.
If the save is a red check box, this is trouble. The save relies on a master file that is missing. Right click and select Diff Masters for a list of what's missing.
So, if you're still trying to figure out what is missing from a certain save and why you get the "some content missing" warning, right click on that save and select Diff Masters. It will tell you what was added or removed between that save and your current load order.
As for the picture, I don't know, but it probably has to do with resizing it into that tiny thumbnail. I wouldn't worry about it.