The dialogue command from customnpcs does not work when DDD is installed and debug.log shows an error.
debug.log

Probably yes, but the better idea is to just check if the problem occurs and assign a default value instead of crashing, and throw a warning in the console.

Seems to be that DDD can't find and attach mob resistances to the NPC, then tries to give a warning about it using the entity's name, which causes a problem with customnpcs because somehow the name doesn't exist or something

So the dialog commands I was testing are /noppes dialog show and /noppes dialog read . The dialogues are drawn from the global pool of dialogues(not attached to any npc) and should show the dialogue in a menu. Normal npc dialog works fine as it is accessed by right-clicking a npc that has dialogue attached to it. Perhaps there is a way to skip DDD's check for mob resistances?