Is the easy mode available in the GOG version? In the manual it says the option is given during the installation, however this doesn't appear to be the case with the GOG version installation. And I don't see any way to change to easy mode from within the game.

Yes, it is, but you have to start it with an other executable than the default one (I currently don't have it installed, so I don't know what the exact file name is, but there's one exe the shortcut points to, and there's an other one - you have to start this other one).

Thanks for the response. Yes, there is a Jackstart.exe (rather than JackOrlando.exe) that allows access to the easy mode.