I have dreamed this night about your plugin ;-) and i got few more possible advancements
1. select box with other widgets (in both show & hide) – so you can set “show this box when that selected box is (is not) visible)” – this could really revolucionalize the usage as you could set all settings just for one widget and the others will just check if that widget is shown or not.
2. possibility to fill both Show/Hide and check if it should be first – “show in all posts and NOT on post x” vs. “do not show on posts except post x”
3. possibility to change ID and class of the box DIV (PLEASE, if possible, it would be my most loved plugin ;) – in that case it could be possible to set other settings, which are normaly common for all widgets (prepending tag, clossing tag …).

anyway i’m glad to see you are still developing it, i worried that it was abandonned.