confused about the license

I have multiple computers that I use regularly, and I was hoping to swap files between them with dropbox. If I purchase a license on Steam, would I be able to use that license on any computer in which I have logged on with Steam? Or is it better to buy the license directly from Scirra and the license is share-able that way?

It's better to buy directly from Scirra.

Also:

Individuals can use their license on as many computers as they like, as long as they are the only one who uses it

From:

https://www.scirra.com/tutorials/57/how ... enses-work

Thank you!