What steps will reproduce the problem?

Use an EssentialsX sign to purchase a wolf spawner. Buy sign:

[Buy]
 1
 52:95
 $90000

Expected output

A wolf spawner correctly identified in inventory and placed as a wolf spawner.

What do you see instead?

Although the inventory label is correct, the SilkSpawners chat info (when selecting the item) shows it as a pig spawner, and it gets placed as a pig spawner with the message, Placing default spawner (either this spawner is invalid or disabled).

Log file of the issue/error

N/A

/version output?

This server is running CraftBukkit version git-Bukkit-d7bebef (MC: 1.12.2) (Implementing API version 1.12.2-R0.1-SNAPSHOT)

SilkSpawners version

SilkSpawners v5.0.2

Please provide any additional information below.

I looked at the NBT data from spawners mined with SilkSpawners and spawners purchased via EssentialsX. I also looked at the Gamepedia Minecraft information. It appears that SS has SpawnData under tag instead of BlockEntityTag. It also appears that SS is looking for EntityId (under BlockEntityTag), but this is not a valid tag at that location. See attached NBT dump.

Checklist

• I am aware that issues caused by /reload are ignored
• If there is a (potential) plugin conflict, I've identified the conflicting plugin
• I have added a valid /version output
• I have added a valid SilkSpawners version
• I have attached necessary information like a screenshot, my list of plugins, config or permissions file(s)
  

Update: I solved this problem by buying the SilkSpawnersShopAddon.