what is "smart" downloading?
 

I have Limewire 4.60 pro and I found a reference to smart downloading, but can find no preference or reference to it in options or anywhere I have looked. It's my understanding that smart downloading will keep trying the download until it finishes. I get tired of going back to use the force resume over and over.

How do I activate "smart downloading"?smart downloading

If it isn't there then it's for a good reason, the reason being that smart dlds continuously send a request to resume a dld until the request is fulfilled. That can quickly inundate the network with such messages, resulting in an overall speed drop. Not good.
I suggest that you don't force resume your downloads: instead, run an occasional search (launching a search every second will have the same effect as smart dlding. + you can't expect 100000 new sources for your file to pop up the next second) for the same file in hopes that LW picks up new sources.