If the 1st suggestion about replacing the incomplete preferences with the older ones doesn't work, then I guess you're stuck with starting them from 0%. I can't think of anything else unless someone else has a suggestion.

Do the files actually start off in your downld window or is your downld window blank when you start up LW? If it's blank & you then go to the LW Library window & Resume them, then chances are they will start from zero. What I'd suggest you do is search for the item again using LW's search, then see if you see one with the open manila folder icon & select that to downld again. It might take time but it's probably the best chance you have. If there's no manila folder icon or cancelled icon (ripped paper icon), then you'd be stuck with the resume from the library.