The solution is easy and doesn't require any additional computer, you can solve it directly in you own:
Step 1: Mount your dmg file double clicking on it.
Step 2: Open the mounted file (as shown in 1 in the pic), then right click on the file GearBox.mpkg (as shown in 2 in the pic)
Step 3: Click in the option "Show the content of the file" (or something similar in english, my computer is in polish :) )
Step 4: You will see a folder called "Contents" ( red 1 in the pic), inside it some file and among them the folder "Packages", open it, then you will see the installator files, double click on GearBox.pkg (red 2 in the pic) and voilá! you can install the program in your brand new mac.
Good luck and keep playing!
