I have always been struggling with this one too...
Up to now the only way was to replace the richtext template or the widget renderer.
New option (added with the last commit):
The individual field configuration can be extended with tiny mce options.
e.g. nive_cms/text.py could be changed from
configuration.data = [
FieldConf(id="textblock", datatype="htext", size=100000, default=u"", name=_(u"Text"), fulltext=True, description=u""),
]
to
configuration.data = [
FieldConf(id="textblock", datatype="htext", size=100000, default=u"", name=_(u"Text"), fulltext=True,
settings={"options": {"mode":"exact", "height": "400", "width": "100%"}}),
]
The result is a minimal tiny mce. ('options' take any tiny mce configuration option)
Arndt.