Nice plugin, feature request to extend its use to all registered objects in Elgg.

which ones are you thinking are missing?

the complexity of the way i coded this is that i over-rode all of the save forms for each of the entity types.. so maintaining it is a bit cumbersome. i am willing to add new entity types if they are useful to me.. and to help others to add their own ones if they want them included.

It is indeed a architectural change of the plugin. But it is possible to query elgg_entitities_subtypes

Based on those subtypes you could extend the forms and allow different containers to post in

I hope I am making sense here.

i am not presently clear on how to extend the forms since they do not have support for extension built into them.. which is why i over-rode them.
do you know of a way?

There is indeed not something like elgg_extend_form. I have to think about it,, if not possible it might be something we should present to the core team on how to to this. Maybe create a default form (most forms have title, description and access_id which could be extended by will.

yes, a wrapper would make sense

Having trouble with this one under elgg 1.9.5/1.9.6  I'm using containers 0.5.2 - tried to upgrade with this one but the link above is still downloading version 0.5.2. The problem I'm encountering is when saving bookmarks. I'm getting this error 

Fatal error: Call to a member function getGUID() on a non-object in /home/content/59/8407459/html/elgg/mod/containers/actions/bookmarks/save.php on line 50

is there a way to fix this?

this plugin is only compatible with elgg 1.8 presently.
a version will be released for 1.9 when it is available. i haven't started with it yet though and there are some enhancements needed. so it may be a few weeks.

OK - thanks! - this is one of my favorite plugins as a site admin.