Captions not displaying correctly

Hi there,

I've been happy with CK Editor so far, but recently I've noticed that sometimes my captions are put to the left, right or top of a picture and not on the bottom. Also, sometimes when I add a caption, the picture itself isn't shown on my blog anymore.
I've searched around a bit and apparently this has to do with the fact that de editor alters the default HTML values for captions on images.

Can this be fixed please?

Thank you

PS: the blog I'm talking about can be found on http://www.wonderfulwanderings.com