Question about challenge compatibility

I thought I would finally give some of the online challenges a try, but when go to download some of them, I get a message telling me the player who issued the challenge has extra content that I do not have and I should go to the GSB website to get it.

So…if I own the base game + tribe and have it updated to the most recent version (1.45?), I am still incompatible with anyone who has Order and Swarm? Or are these challenges just modded and the game thinks they are new content?

its only incompatible if the player issuing the challenge leaves the box ticked saying they are using content from those expansions. The problem is many people forget to untick them. It’s a bit hacky, and ultimately the server should be able to set those flags automatically, without any mistakes or relying on the player to set those flags correctly.

I see. Is there any chance that different versions of the game will be more compatible with each other down the road? i.e. players without race X can still play against it.

…or would that require all copies of the game to contain the DLC locked away in the files? (not a very popular method)