Introducing new fonts

["Duncan Hothersall" <dh@capdm.com>]

I'm having lots of trouble introducing a new body font in ConTeXt. Before
streaming out my woes, I wonder if anyone recognises my symptoms as being
due to a common mistake:

My output has the correct fonts, but all the character spacing has gone
caput. Basically every character is set in a tight box, spaces don't show,
and vertical space between lines and paragraphs doesn't show either.

I've followed the steps set out in a previous message on this list about
installing a new font
(http://ml-archives.mini.pw.edu.pl/ntg-context/msg01903.html). I picked up
an already generated set of tfm and vf from the web. (Do I need vf for
ConTeXt?) The font is Bitstream Souvenir (Light and Demi).

This feels to me like a TFM problem, and I'm desperately fiddling, but if
anyone recognises this as a particular type of obvious boo-boo I'd be really
grateful for a pointer.

Thanks,

Duncan