The user-interface of L3DT v2.4 beta2 slows down dramatically after extended sessions, as a result of improper font cleanup in some dialogs and wizards. This will be fixed in the next release, but if you can't wait, then you can fix it this way:
- Select 'Settings->Windows' in menu.
- Open 'Commmon->Fonts->StdFont' in tree.
- Double-click on 'UseSystemFont' (setting it to true).
Cheers,
Aaron.