[Jim Chapman]

[note: all these points are addressed in release 1.0: see page 6 of this thread]
Yes it supports centred text alignment, as well as left, right and fully justified. It follows the directives in the ePub document itself. If there's a demand for it, I could add a feature whereby the user could over-ride (i.e. "justify paragraph text even if the ePub says not to"). Those with a strong view, please message me, and I will consider it.

In terms of full page breaks, it will insert a full page break at the start of a chapter (this being the normal way that the ePub format signals a page break).
As it stands, the program renders the <br> tag as a centred "=O=" followed by a line break. I did that because I reckoned that by and large it was better than adding loads of page breaks (some ePub books make pretty heavy use of <br> breaks). But if there is a lot of demand for rendering them as page breaks, it's an easy option to add. Anyone with a strong view either way, please message me.
[see below for correction - I mistook hr and br]
Cheers,

Jim