Hello.
I did a quick search in the documentation but i couldn't find a section describing the upgrade process from 1.5 to 2.0. Is there one somewhere?
In addition to that question, is it possible to have two separate sites (one with 1.5 and one with 2.0) which use the same database?
The documentation is here: https://doc.mimec.org/webissues-guide/system-administration.html#updating-webissues
No, it's not possible, when you upgrade the database to 2.0, the 1.1.5 version will no longer work. You can create a separate environment and clone the database if you want to test the upgrade first.
Regards,
Michał