I’ve been enjoying playing the Barbarossa Brawl but I can no longer change the game speed per my hotkey and the difficulty is fixed at hard, no matter what I set my campaign difficulty to.
Is it just me? Being a bit older than most players I can’t play at a high APM so this is a let down for me.
I can’t play any of those challenges, because I can’t pause in them. I am a slow analytical thinker and need pausing for thinking and issuing orders. Gameplay is for me just too hectic and unenjoyable without ability to pause 
Why is pausing not allowed? There is no public leaderboard now anyway, so who cares if I pause while playing the challenge?
It might be nice to have separate “practice” and “competition” modes. Where practice allows for changing speed, pausing, using cheats, saves/loads, etc. Then “competition” mode locks it at Hard difficulty and Normal speed without cheats/pauses, and then only the “competition” one counts for the leaderboard (or event unlocks).
If you like what you can do is extract the Challenge Campaign into a Custom Scenario and then you can do saves and pauses, as well as change the triggers to for instance give more time. Your scenario will then be stand alone and not update the score.
There are instructions by TWest on YouTube on how to do this.
I just realised that you’re the TWest I mentioned in my reply to Yorok0!
I do agree with your suggestion.
Probably it was meant to be a just one setting scenario. So the devs thought it was a bug that you can change the speed or difficulty.
Nevertheless i support the idea of KayneTWest.