Try deleting the file from the dwnld pane & re-select to dwnld from the search results. Do another search for sources & repeat process; deleting & reselecting multiple times b/w each search. Eventually it should kick in & dwnld.

I don't know which version of LW you have but by forcing resume for a large quantity of files, it can put great stress upon the connection quality. This is b/c each one queues & takes it in turn whilst they search for sources every few mins. Also attempting to dwnld too many at one time can have an affect upon dwnlding results.

Please do this TEST (click on link) See image below that article for closer understanding. Is your result 'True' or 'False'?

Optimise your LW settings: Link 1 (click me) and also Link 2 (click me also) and also Search & dwnld techniques (some hints)