Some formating and more tags won't show

Hi,

I’m facing a problem on my self hosted wordpress site- mrhandley.co.uk

In my posts, some formating won’t show, for instance:-

<more> tags won’t show
New paragraphs, or blank lines won’t show (using < br> etc)
An example of a page which has a <more> in it is https://mrhandley.co.uk/2010/12/a-few-technical-problems/

The more tag stays in the HTML view of the post.

And which is meant to have paragraphs in is
https://mrhandley.co.uk/2010/12/wintersnow-by-florence/
There is no evidence of the paragraphs in the html or WYSIWYG view- and they get stripped out of the WYWISWG views when posts are saved/updated.

I’m using the latest version of the Mystique theme, but I have tried defaulting back to Twenty Ten and the formating/tags still won’t work in these pages.

I have the latest version 3.0.3 of WordPress standard install.

I’ve tried disabiling all plugins and this did not resolve the issue.

I’ve also tried automatically re-installing the WP installation- again with no success.

I’m not quite sure what else to do- any help would be greatly appreciated!

Thanks!