Sadly, the sharing of modules doesn't seem to work in the latest version (v8) of CE. Pages/modules from other portals appear in the dropdown pick list but they can'e be added to the page - nothing happens when trying to do so.

Hi Sebastian. I just did so that it could be ruled out - it results in the same behavior. Everything "works" except for the actual instantiation of the chosen module on the page.

It's strange to me that there isn't an extension that fills the need to share HTML modules across portals on CE. Sure, it's easy enough to develop, but one would think there'd be a commercial or open source extension somewhere that already does this. There isn't. And I mean one that could be put into the hands of a content administrator.