I have an incomplete file of 845mb that needs another 10 to be complete. When I right click and click "resume" it goes into search with 0mb. How do I get it to resume with 845 mb? Also how do I search for "Whats new"

When it actually starts to download it will show the correct %. Best to use a manual search & use same search terms you used originally. Then Right click the search tab & choose Get More Results.

For what's new type seach, you need to click that tab. See sample image below, though it will look different for windows version LW.

I tried all that but it still started over at 0% after it was at 99%. It shows 8454mb in the incomplete section of the library.

Is there a way to automatically have files resumed once they "Need more sources" ?

no. But in any case, LW does periodically (about once every 30 or 60 mins) search for sources for them.

If LW was auto searching everybody's incompletes all the time, it would flood the network & the heavy traffic would drag it to a crawl. So LW tries to be careful to use those types of functions in moderation.

Thanks for that. Still wondering how to complete the download. It has the same title and size but the incomplete started over even though it is showing 845mb in the library.

Re-search the download using same terms you originally used. Then hopefully you will see both as separate downloads. There may be limited no. of people with that first one. Thus you may need to wait until they come online/you can locate them/they have free upload slots. Don't forget you can right-click a search result tab & choose to Get More Results.

BTW re: incompletes resuming from incomplete folder at correct % depends on the version of LW you have. It was introduced about a year or so ago to ensure it would do this. Earlier versions didn't & would instead resume at zero %.