Hi adeibiza,
Thanks for the great post!
Unfortunately the print to web conversion defaults to converting text boxes to images and it's a default which cannot be changed via a preference or some other automated process. You will have to convert each text box individually.
The easiest way to do so (that I have found) is using the item tool, double-click the text box. You can simply uncheck the "Convert to graphic" checkbox in the bottom left of the dialog which appears. Now, you will probably immediately notice that the text resizes and reflows, so some adjustment of the size of that text box and some copyfitting will probably be necessary.
The reason we convert text to graphics by default is mainly to preserve the print fidelity and any print specific typographic features (e.g. some typefaces, kerning, leading, swashes/ligatures, etc.) which may be applied to the text in a format that will display correctly on the web (i.e. and image). This is one big area of difference between web and print designers... Web designers usually just accept text reflow as no big deal because the browser's displayed page size can/will simply adjust and they account for it in their designs... whereas print folks tend to need exact control over text flow since their layouts are physically size restricted to the paper size. Since QuarkXPress is primarily a print application, we tended to lean toward the print designer's viewpoint.
With that said, your request for a way to do this automatically for an entire layout upon conversion to web is a great feature request for the Web Layout space. I have noted it and will be sure to try and get it into a future version.
As for application of a default stylesheet for web, this is a little tougher because the application currently doesn't have a way of knowing what content needs to be styled (like say a body of text) and what information needs to preserve its styling as it is (like say a headline, callout box or caption). Right now we are working on ways to make our layouts more intelligent to accomplish this type of thing, but currently we don't have this capability.
I wish I had better answers for you but thanks again for your great post!
-Drew
Drew Bartlett (Quark)
Technical Product Management - Desktop