It sounds like you're trying to downld large files, such as video files. See if these links are any help to you (same principles as LimeWire): 1.
Cant search well help, & also see the following link & follow “ALL” the off-shoot links to find hints & extra skills to help solve your problem:
To continue files downlding (click on link)
BTW Do this test:
Bug Report instructions & sample image Is the result True/False?
BTW there are some clients out there who are known to be unreliable & slow. These are most commonly Shareaza (RAZA) as they often use most of their upload bandwidth for other networks. This is at the sacrifice of gnutella users. You can check, right-click the top of the downld columns & choose to view Client/version. This will show whether you're downlding from LW, or FW or RAZA or other gnutella client programs.