[dkplayaclub]

I like to edit my epubs with Calibre so that chapters, or the beginning of short stories in collections, always start on their own page. It just makes reading and bookmarking all that much easier.
I came across an odd issue on one of my books last night though. In the editor i pick the split tool, but the green line that represents where the split would go does not show up in the place I want to split. What would cause this? Is there a workaround, or another way to force a split?
Also, is splitting the epub repeatedly as I have been doing not even the best way to do this? Any input would be helpful. I am pretty new to this.