Hi Pierre,
I see what's going on here... I put an updated version of WDS
on the Guide 9 DVD, but the .tdf is pointing to the old file which
no longer exists!
To get around this, download
http://www.projectpluto.com/wds_new.tdf
(about 8 KBytes) and put it in your Guide folder. You'll then have
a "WDS (current)" entry in your list of user-added datasets.
I'll make sure the next update includes this fix.
You mention datasets being cut off after U. What datasets did you
have starting with W or later letters? (There are some, but the
ZC and XC catalogues were provided separately, on the "extras"
page of the Web site.)
-- Bill