So I heard that 0.15 just came out recently. I am assuming it is the unstable beta version. When I go into steam and select the beta dropdown menu under factorio's properties, nothing comes up. I just click the drop down menu and nothing happens. Is this because my computer doesn't support betas? Can somebody please explain?
I have the same problem. Drop down does nothing on one computer but works on the other. In my case though I need it on the computer that it isn't working. It is a 64bit computer and all opt betas on other games are working.
You can also just get the betas directly downloaded from Factorio site. Just link your Steam ID to your Factorio ID (look at FAQ how to do it because idr). Then you can do a direct download which seems to fix the problem that some people (including me) are having with 0.15 launching through Steam.