Hi Martin,
I have setup a fresh Wiki with the most recent version of DokuWiki. I have installed IndexMenu2 plugin, the remotescript plugin and set an example of how the navigation mode for IndexMenu2 is not working in the page named sidebar. I have also removed javascript and CSS compression in the configuration settings. You can view this here:
http://dwtest.davidium.net/doku.php?id=start
I have set admin account usr/pwd to 'admin'. This test Wiki is running on the same shared host as the other Wiki's I am having trouble using IndexMenu2 with and it is behaving in exactly the same way on the Test Wiki.
Regards,
Dave