Several months later, I’m pleased to report that I’ve finally found a work-around to fix the render issue with the Star Map seen through the diving suit faceplate. It’s a little outside the box: I replaced Manaan’s Star Map placeable with a stationary NPC (essentially a turret) which looks exactly like the Star Map. I was inspired by this thread, which mentioned making placeables into NPCs as a way to get around the appearance.2da row limit bug. That plus changing the faceplate TXI to "blending additive" (suggested by DarthParametric back when I originally released this) finally made the Star Map render correctly through the helmet:
I have updated the mod to include this fix along with a few other minor tweaks. I have also switched over to HoloPatcher for the installer—thanks a ton to th3w1zard1 and Cortisol, who spent a lot of time upgrading HoloPatcher’s script compiling ability to handle the scripts in my mod.