How do you install griffon version 2.5? If I run
sdk list griffon
it shows me version 1.5 as latest version.
Griffon 2.x is not available as an sdk candidate because it no longer has a command line of its own. You either use gradle or maven to build Griffon 2.x projects. You have the option to initialize a project using lazybones however that's not a hard requirement, you can create the project from scratch if you like.
Be warned that IntelliJ has a Griffon plugin. This plugin does not work with Griffon 2.x (http://griffon-framework.org/tutorials/1_getting_started.html#_tutorial_1_4) and its usage is discouraged.
AFAIK there's no lazybones support in IntelliJ for project creation.