You are correct Photopost will use CSS and templates next version. My hack only does one style. However I am writing up a small chart for those that dare to convert CSS in Photopost. The changes are too intensive to list an exact hack but this is not that hard. I have done this on my site to all the major files so that people can change stylesheets and Photopost changes. It is a simple but time consuming thing but anyone can do it. Example below:
bgcolor="{$Globals['bordercolor']}"
would be
class="tableborders"
or
bgcolor="{$Globals['maincolor']}"
would be
class="darktable"
or
bgcolor="{$Globals['headcolor']}"
would be
class="tdheader"
Like I said I am going to write up a short comparison so those that want to do this can do this and this should provide full integration until Photopost catch's up with the CSS and template thing.
I got ya covered Msula I know a die hard Photopost guy like you wants the whole thing.

Let these guys digest the first part and they can finish for multiple stylesheets next. I will have a comparison probally tonight or tommorow morning.