I see two problems here. First in Zentools2 I cant find a field to override the text. Second that on the other hand should not be necessary anyway because "read more ..." is a globally availlable language string and should be translated automatically according to the site language. I face that problem at laengenfeldschule.de/index.php?lang=de

You have the choice of both in Zentools2.

- Click custom more text?
- Enter the custom more text

If the custom option is not selected then it will reference from your language file.

"If the custom option is not selected then it will reference from your language file. "

That is not true. It always uses English (in my installations).

... and it used to work for the second to last version and the last version of zenzools2 but not in the current one I have installed: 1.1.3 from February 27, 2014.

I've just installed 1.1.7 in a fresh installation and the Danish language pack and the readmore is converted to Danish.

Which version are you using specifically? 1.1.3 is not the latest - v1.1.7 is the latest.

1.1.7 does not have that problem indeed. I just wonder why this update never showed up in the Joomla Update section. Other commercial extensions do not have that problem on my installation.

At the moment zentools2 isn't available via the Joomla update service

Cheers
Paul

... that is really bad practice IMHO.

It will be I believe at some point

Happy Christmas

Cheers
Paul