Yes that is often the story with FrostWire. You could try copying the gnutella.net file from the FrostWire preferences folder across to the LW preferences folder and replace the one that is there. That might make a difference.
Another thing to try might be copying the entire contents of the FW prefs folder across, though FW's preferences folder tends to be a little different so might have odd results.

I have the free version of Malewarebytes installed on one of my Windows XP's, so that should not be a problem.