Hi! Zorin's terrific for doing work, but not for gaming. I'm going to try a dual boot with Mint.
Can I add Mint to the same hard drive I've installed Zorin, or do I have to reinstall Zorin and install Mint? How much is required on the swap partition?
Or, can I install mint on an external hard drive? Running through a USB 3.0?
Can I install Mint into VirtualBox, along with the gaming apps?
Yes, it's the same one recommended but Zorin. You can set up a swap partition, and both os's can use the same one. The recommended size is half of your ram size, so we cannot tell you what size it should be.
I Mentone the minimum recommended. Anything above that is dependent on how much ram your machine has. I have 32gb and never use it all. Having a swap partition is unnecessary the more ram you have.