I'm using the PC e-reader version 18.104.22.168 under Windows 7 and trying to read Under the Dome. No quote marks are showing up in the text at all, which makes it fairly difficult to follow conversations in the text. On my Nook, the quotes show up fine using the exact same eBook, purchased from B&N.
Random: this has been noticed before, and seems to be a problem with that particular book. Other books show quotes ok. I seem to remember one other book had a problem, but Under the Dome was specifically mentioned.
I'm not sure there is a fix, other than reading it on the nook.