Timeframe for what? The infinite redirect issue has been resolved. You should be able to create Joomla menu items to categories or groups fine, but your modules assigned to those menu items are only going to be displayed when those specific menu items are accessed. If you need a module on a category or group no matter how it's accessed there isn't really a solution for that beyond acting on GJ triggers and trying to insert the module into the page or making a custom GJ template that outputs modules.

We do not provide timeframes here. I've no idea when that will be fixed. It has not been an issue until now. I was only able to duplicate the infinite redirect. The rest of your issues I am unable to confirm. CB Activity is supposed to be using that menu item so that is working correctly. I will be reviewing the router again once I get to that ticket when I find time, but right now fixing Install from Web is a priority as it keeps failing for a significant amount of people.

I strongly doubt it as CB Activity is using the last GJ menu item published ! Which brings to lots of 404 errors instead of using the main category menu (for instance All Categories or All groups)

Disable SEF and check the Itemid it's using in its URL. Then match that against your menu item. This will tell you exactly what menu item it is using. I believe a see the potential issue though. Joomla menu URLs don't include "func" and func=show is being set on the URLs, which will cause the lookup to fail. Right now it's not possible to implement OR cases for our Itemid lookup. That's something that we need improved in CB itself. In reality we just need to completely rewrite and improve routing behavior. Plugins also need to move away from using func and just consolidate it in action so instead of &action=categories&func=show you'd have &action=categories.show or more appropriately for a category you'd have &action=category.show. So a couple of things need to happen to improve the rewriting. Plugin routing is still in its infancy and only a few plugins are actually utilizing it right now.