Dial up is limited. Since your bandwidth is so small & is shared between upload and downloads. Thus an overall capacity of download/upload total at between 5-7 KB/s.

Make sure Windows firewall is configured to allow LW full access.

When upgrading to LW Pro, it's a good idea to delete the LW preferences folder; Try deleting your LW Preferences folder whilst LW is closed; instructions here: Point #2 & 3 in Fixes for Limewire (sample image included at bottom of page.)

LW Basic connects to 3 ultrapeers, LW Pro to 5 ultrapeers. On dial up there may be some difficulty maintaining the connection to the 5 ultrapeers.

On dial up, don't do too much at one time. Try not to download too many files at once. Don't use the Resume button on all incomplete files. This can have side-fx such as affect LW's connection quality. May queue your files for much much longer.