REI shows deathcompass in normal compass crafting recipes, however causes a CTD when placed in the crafting grid.
Causes another CTD when attempting to take it back out.
Only affects client, not servers.

Ah, sorry I didn't see the email that this got a reply.
This is the report I recreated just now. The pack is Benchmark 2 on version 0.6.3
https://pastebin.com/zdANv30H

Logs or something?

Do you have any logs? Or at least consistent steps to recreate that