1) LimeWire is searching for the file name.
2) LimeWire leads you to believe it was requerying the network every 5 minutes, - that's not quite true. - If you are trying to download 10 files, LimeWire will be requerying every 450 minutes, no matter what the gui says.

I don't think the LimeWire team would consider a requery interval of 30 minutes as acceptable, but they are working on another feature, that would help you finding alternate locations.