Crash when previewing a structure with windmill blocks

[TheOddlySeagull]

Context Environment

Minecraft version:
1.12.2

Ancient Warfare 2 version:
ancientwarfare-1.12.2-2.9.8.

Minecraft Forge version:
14.23.5.2859

Link to your crash log (if the game crashes):
crash_report_and_logs.txt

Problem

The preview of windmill multi-block is broken. it crashes the game.

Expected Behavior

Preview of the structure before spawning it, with the windmill block support.

Current Behavior

Game go ouch
the game stops responding, then crashes. No preview at all

Steps to Reproduce

1. using structure builder, select a structure with windmill blocks (ex: NoggWindmill2 | Seagull's WorldG Structure Pack, or SB_MarenCol_WindMill_1H2R_1_acacia | Seagull's Survival Structure Pack)
   Here is a link to download one of them: http://ancient-warfare.legends-of-gramdatis.com/html/structure.html?structureName=Seagull%27s%20Survival%20Structure%20Pack/SB_MarenCol_WindMill_1H2R_1_acacia
2. Ttrigger the preview by looking at the floor
3. Admire the game crash

Possible Solution

In the preview, show either the unanimated windmill blocks, or the animated model, or nothing at all. Any is fine.