To be honest I haven't looked at that code or any elgg code for almost 12 months. It was pure chance that I even popped by today. I've not got the time to look through it for you. If you take some time I'm sure you can work it out.
EDIT: from...
The conversation plugin changes the way internal messages are stored in the system. Instead of saving each one as an object it creates an object (conversation) and saves messages as metadata (comments) on the conversation object.
It's an old plugin...
They only other solution would be to save two different sets of tags. An English version (tags_en) and a chinese version (tags_zh) and then pull up the relevant ones depending on a check of current user's language.
It will become fiddly for users...
He means that the only type of files that display when looking at them are pictures. This is default elgg without any zaudio, video player plugins enabled.
Create a plugin hook for pagesetup with a late priority and pull in the breadcrumb, then inject your extra one to the beginning and return the breadcrumb to the page.