Re: Extend the page tabs width?
Not really, it’s more complicated than it need be for a simple property adjustment but thats the way of things, creating a child theme is a good idea even though fairly involved – once done you’ll realise it’s not really – it will allow freedom to adjust/overwrite further styles set in the default theme without fear of your changes being overwritten, also if things go wrong simply re-select the BP-default theme in the dashboard.
As for the width issues and IE I’m not really sure why max-width was used, as David says default theme is not IE <8 friendly but it ought to be and could be quite easily, state width as 'max-width' & 'width' to keep IE happy.
