I'm not so sure if the Ancient Odysseys Conflict Action Map works perfectly as is for D&D and all of it's offspring, but it does plant the seed for a compromise between the Battle Grid and the Theatre of the Mind world views on running combat encounters.
My feeling is that the CAM as presented doesn't offer the GM enough options for adversary placement. This could be addressed by moving the enemies in combat to the lower edge of The Enemy section, leaving those not engaged or using missile / spells in the middle of The Enemy section and moving any engaged in a backstab styled attack on the right side of the section. I'd reserve the top of The Enemy section for enemies that are engage with PCs attacking from advantage.
Still, I think there is an OSR styled CAM residing in the mind of one of the readers of this post that would address the needs of a D&D styled game and still maintain the simplicity of the Ancient Odysseys Conflict Action Map.
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The Minotaur for Old-School Essentials
*Requirements:* Minimum STR 9, Minimum CON 9
*Prime Requisite:* STR and CON
*Hit Dice:* 1d10
*Maximum Level:* 8
*Armor:* Leather, including shield...