Merge two 2.3 Installations

hi there, we are using 2 different installations of Piwik 2.3 and want to merge them for better maintenance.
I started to import the sites form one to the other. Luckily I used different ID for the sides in both installations (it was a single installation before).

First: the imported sites don’t show up - what can I do? Is there any other place to adjust this?
Second: I would now start to import historical data in the tables. Is there anything I should be aware of?

I realized some solutions in the net but for 1.9 only.


What I can say is that: we are working on a tool to help migrate one website from a piwik instance to another instance. At this stage the tool is not ready yet…