It crashes now because of anticheat.
I have over 200 hours with Metal Slug Awakening on the LCD Steam Deck. I have never been able to play it on a OLED Steam Deck, it just crashes. I used the 7.0-6 Proton because it works best with the touch screen. It does work on the newer Protons and actually runs faster on boot but the touch screen needs first tap like your placing a mouse cursor and than a second tap to execute it. With 7.0-6 I only need one touch but on boot it has some weird slowdown, like it's waiting for something but than it just runs.
But why those the OLED version not work, I have no idea. It just crashes after the starting launcher.
I have had one problem with the LCD versions was when there was a Time change, for some reason, the Desktop time was set to Dublin and when I changed it to Lisbon (I'm from Portugal), all worked again. But there most be a bug in the Gamescape because you can't change it there. For exemple, mine is set to Lisbon on the Desktop and in the Gamescape it's set to somewhere else. Clearly there is a bug that both Gamescape and Desktop doesn't bind. Could this be the problem on the OLED versions?
Another game I have encountered that also doesn't work with the OLED Steam Deck but does work with the LCD Steam Deck is Delta Force (Steam AppID 2507950) which is also from the TiMi Studio Group as Metal Slug: Awakening. Coincidence?
Could this be their anticheat, where they forgot about the LCD Steam Deck? Could this be something else?
By the way, here is my post (very top) at ProtonDB about Metal Slug Awakeing: https://www.protondb.com/app/2963870
Nothing extracted yet.
Compatibility Report
System Information
I confirm:
steam-2963870.log
Symptoms
The game is crashing with a permanent black screen after having clicked Play on the game's launcher window.
Reproduction
Just launch the game, click Play on the game's launcher window.