Character's skin returns to default in inventory when dead.

NOTE:~ I am playing a custom map, Sky Grid, by SethBling.

What I expected to happen was...:
In your inventory when you're dead, it should show your characters skin. Not the default. But it didn't

What actually happened was...:
In my inventory it showed my skin for a few seconds, but then changed to the default, Steve.

Steps to Reproduce:
1. I did it THIS way. I fell into the void (by accident) then I opened my inventory to see what I had, but then I died.
2. My character fell down red (Red_Fall_Down picture) But then changed to default. (Default_Red_Fall_Down picture)
3. But I closed my inventory and hit respawn (I want to mention, about 13 deaths later, the 'Respawn' and 'Title Menu' buttons wouldn't let me respawn.)