Actually, you have it backwards... I'm assuming the trackball works the same way as a mouse, and if so then in X2, lassoing notes is done by right-clicking and dragging.
In any case, no, unfortunately, none of the tools can be customized. Hopefully, we'll get that functionality back in a future version.
In the meantime, the software for your trackball might allow you to change the behavior of the buttons, etc.
Scott
--
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