Hi,
We have  a game that we want to sell, but its run on Steam environment.  We  have Steam Cloud, Steam online subsystem and other Steam features like the Steam beacons because we are developing the multiplayer. We do not care for DRM, only steam features.
We know that Itch.io guidelines prefers to sell files with the game, and we want to offer something like that, but for now, our game depends on the steam environment.  We will add a free demo very soon, but we are working in more content and multiplayer. 
We have written 3 mails to support@itch.io asking how should we proceed. No response at all.

We could upload a standalone build (is more than 1gb, we need permission to do that too) it would not have all the features and would not update  without steam. Of course it will be sell with a steam key for the complete game.  Is that appropiate?

Thank you