You could try going to LW's tools > options > advanced > super really advanced > performance. Tick the boxes to disable ultrapeer capabilities, disable connecting to DHT & disable TLS. Click 'ok'.
If things are still stuffed, you can always go back to LW 4.18.8 There's a page to download old installers:
Lime Wire » Download Out-Of-Date Installers
If you're using Pro, your personal download page has a link to 4.18.8 on the left hand side - 'Get LimeWire Classic'.