I can't install new themes

[Ed Crossley <ed crossley ntlworld com>]

Hi
I'm using Mandrake 7.2 and I've just updated sawfish because of that
background image bug. However, now i can't seem to install any new themes.
I click on the control center, then theme selector and i'm told i only have
the default theme installed. I then click on "install new theme", navigate
to where i've downloaded them to select them and hey presto, nothing!
Looking in my home directory, there is a .themes directory and in it are
the themes i've supposedly "installed". However, back at the theme selector
screen, still just the default theme installed. Is this a bug? is it
something i've done? Can i correct it?
Thanks for your time and help

Best regard 
Ed.