I think that since plone 3 used tables as the main structure of the page, while plone 4 uses sunburst, which uses Deco GS.
Probably the fastest way (and not way: P) is to force the width of the columns via CSS (you can click CSS using style_slot in base_edit.cpt).
Anyway, I see in
./plonetheme.sunburst-1.0.3-py2.6.egg/plonetheme/sunburst/skins/sunburst_templates/main_template.pt
that the class / width columns should be computed by getColumnsClass
sunburst_view
. This is probably a bit of a buggy (I did not debug it, though).
NTN
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