It seems that I have discovered some problems with XFig. :(

I have tried this simple test.

$ /usr/bin/xfig &

then I have drawn a box with 'Rectangular BOX drawing (b)'. After this, 
I have saved the figure (with: File | Save 'test.fig', it is attached).

Now if I exit from XFig and restart it (/usr/bin/xfig &), trying to 
'Open' (Meta-O) 'test.fig', I got the error:

=============
File test.fig:
Figure resolution or coordinate specifier missing in line 5.
======================

Examining 'test.fig' with an editor, the line 5 contains: 100,00. So I 
remembered that I have

$ echo $LANG
it_IT.UTF-8

(I do not know which Windows application has set that as system env. 
variable.)

I tried to change 100,00 ==> 100.00 (test2.fig), but still did work. So 
I have tried

$ export LANG=us_US.UTF-8

Now, when I start XFig, I got

$ /usr/bin/xfig &
$ Warning: locale not supported by C library, locale unchanged

but, repeating all the above, XFig seems to work correctly: I can create 
and read, with XFig, 'test3.fig' (though, XFig still does not read 
test2.fig!).

So, it remains to clarify WHY, with LANG=it_IT.UTF-8, it does not work 
right.

Ciao,
Angelo.