Hi Carlo, If I understand correctly you cant view the maps? it shows an error? If so then its not an issue with the version of Java.
First, java plugin is not supported in chrome so you need to use another browser.
Second, you need to go to configure java (its part of the java download). Go to the security tab click the edit site list. You will get a pop up, then click the add button and you should be able to add the ip address of the ZD.
Be sure to put in the full url like this https://x.x.x.x then click ok then ok again
close your browser then reopen it.
You will get some java messages hit ok or ignore (i forget)