[Therion] Changing map-legend /cavelength

I have a plot that is fine but the cavelength in the map legend is wrong (because the .3d file used if for the whole system, not just this part of it). HOw can I override this value, either by changing the value for \cavelength, or by simply putting some text in instead. I tried to follow the examples in the back of the thbook, and succeeded in replacing the whole map legend with nothing but a north arrow in the top NW corner (as in the example), but I don't know enough latex to put back in the title, legend etc in the right format or how to add some plain text. Wookey -- Aleph One Ltd, Bottisham, CAMBRIDGE, CB5 9BA, UK Tel +44 (0) 1223 811679 work: http://www.aleph1.co.uk/ play: http://wookware.org/