Crashed while attempting to place scanned structure from Ars Additions

Is there an existing issue for this?

• I have searched the existing issues.

Are you using the latest Structurize Version?

• I am running the latest beta/release version of Structurize for my Minecraft version.
  I am also running the latest versions of other mods that are part of my problem.

Did you check on the Wiki? or ask on Discord?

• I checked the MineColonies/Structurize Wiki or I asked on discord.

Minecraft Version

1.21

Structurize Version

1.0.790-1.21.1-snapshot

MineColonies Version (if related bug)

1.1.1154-1.21.1-snapshot

Related Mods and their Versions

NeoForge 21.1.211
Ars Nouveau 1.21.1-5.10.6
Ars Additions 1.21.1-21.2.3
BlockUI 1.0.206-1.21.1-snapshot

Current Behavior

Not honestly sure what caused this crash so wanted to share it in case you saw something that could be fixed on our end.

I successfully scanned a large structure from Ars Additions which includes vanilla blocks, Ars Nouveau blocks, as well as Ars Addition added blocks. The structure in question is their Arcane Library.

When I tried to then place the scanned structure the game crashed. Mind you, the author of Ars Additions is a bit of a damned mess as a coder, uses mixins, lots of log errors, so this may be on their end as far as wtf is wrong with why Structurize choked, but on the offhand that it's an issue we can work around then better to eyeball it, yeah? Crash log attached.

What little I understand in the log is that there is a block (or likely multiple blocks) that are registering as null. Not sure if there is a way Structurize can work around a null block.

crash-2025-10-23_11.31.06-server.txt

Expected Behavior

For it not to crash

Reproduction Steps

Explained in Current Behavior. Scanned a structure, attempted to then place said structure with build tool, crashed

Logs

gist is still giving me an error any time I try to use it for crash reports so I will attach it instead

Anything else?

2025-10-23-2.log.gz

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Start by reading the attached crash-2025-10-23_11.31.06-server.txt and 2025-10-23-2.log.gz files, then reproduce the crash by scanning and placing the Ars Additions Arcane Library with the build tool. Trace the reported null-block failure through the Structurize scanning and placement process, and determine whether the crash is in Structurize or a related mod. Done means the ownership and a reliable fix or workaround are established.