Hello. I have ran into the same problem. I was in the Nether and was killed by some Blazes (no surprise there). Anyways, I spawned back into the house beside my bed as normal but when I opened up the inventory to start crafting equipment again, the game force closed. I tried changing the keybind to different keys and even uninstalled Minecraft: Windows 10 Edition and the problem still persisted on the realm. I know I don't have a reproduction map written down, but I'm not entirely sure how to do make one. But below is a link to the Minecraft Realms world in which the problem occurs.

https://drive.google.com/file/d/0B4uvSeOhkJxyc3BpcG83dk9WeDg/view?usp=drive_web