@marikane - Are you referring to the Gallery menu item not being available in the Dashboard sidebar and/or no IGW (green button) in the Visual tab of the editor?
If that is the case, then you may need to use our external Reset Tool plugin to help sort out this issue. Please submit a Bug Report (http://www.nextgen-gallery.com/report-bug/ ... please reference this topic) with your site details so we can get you the Reset Tool.
Thanks!
- Cais.