Let's see what suggestions Stief has. At this point he is not using LW 5 however he might have some suggestions all the same.

My only other suggestions would be to remove the install limewire.pkg file from the library folder & reinstall LW. Receipts folder sample image. Other than that, trying LW in a separate account to see if same problems. And last suggestion would be downgrading to LW 4.18, however let's see if Stief has any suggestions first.

Oh ... one more suggestion, go to menu bar, top-left corner click on Apple icon & you will see a menu appear. Choose Software Update to see if any updates are ready for you. Sample image here Updating Apple software such as Java.