Steam key vs. License key

Hello everyone,

I have recently purchased DeskScapesvia Humble Bundle. It offers me to choose between Steam key or License key, but I wont be able to change my choice.

Here is my problem: I really want it on steam, because it would be easier for me to keep when I switch machines, but I dont usually keep my Steam account logged on, or another steamaccoint can be loggen on, so in this case separate license could be better when Im on another account.

My question is towards users who have their Steam keys:

Does installed Desk Scapes (and also Fences) function if Steam is turned off?