Hello,
Thanks for pointing this issue out to me! I’ll certainly look into it further and see if I can get a solution pushed out as an update sometime; until then, would it be possible for you to try using a different plugin? The Jetpack by WordPress.com plugin for instance should allow you to create a Twitter widget without anything being cut off.
If you do choose to use Jetpack, once you activate the plugin and connect to a WordPress.com account (the plugin guides you through connecting/signing up for free if you don’t have one already), you can simply go back to Appearance –> Widgets in your WordPress dashboard, and there should now be an option to add a Twitter Timeline (Jetpack) to your sidebar.
I hope this will be an okay solution for you while I try to figure something more generic out, too! Sorry for the inconvenience and thanks again for bringing this to my attention!