Create 0.5.1 Double Slabs compatibility broke

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Describe the Bug

Since the Create 0.5.1 update compatibility with the Mod Double Slabs is broken and leads to crashes.

The Double Slabs mod allows you to combine different slabs in a single block.
The compatibility issue appears when placing combined slabs through a schematic in Creative mode. Before the Create 0.5.1 update this worked without issue, all combined slabs got placed correctly.
In Version 0.5.1 or newer, when trying to place combined slabs with a schematic they turn into a block with missing textures that instantly crashes the game when interacted with.
The only way to remove these bugged blocks afterwards is with commands or Worldedit

Trying to place the same schematic with the schematicannon just skips the combined slabs. this was the case before 0.5.1 as well.

Reproduction Steps

(Do this in Creative mode)

1. Place two slabs into a block. (Any two that combine using the Double Slabs mod, the slabs can be different or the same)
2. Turn that block into a schematic.
3. Place the schematic.

Expected Result

The block that gets placed is missing textures and immediately crashes the game if it is interacted with in any way. Trying to break or even step on the block crashes the game.

Screenshots and Videos

It doesn't matter if the slabs are of the same block or not, any slabs that get combined with the Double Slabs mod cause this issue.

F3 info of the blocks.

Making the schematic.

The preview before placing the schematic shows the blocks correctly.

As soon as they are placed they turn into this.

F3 info of the bugged blocks.

Placing them with the schematicannon just skips the offending blocks. (this was the case even before Create 5.1)

Crash after jumping on the blocks.
https://github.com/Creators-of-Create/Create/assets/120684222/014116f1-9ecd-4358-ba3f-3ea1b946e373

This problem only started with Create 5.1, the following screenshots are from 0.5.0i. It works correctly here.

I have a lot of schematics that use Double Slabs so this is pretty unfortunate.
(How it is supposed to look vs how it looks after placing)

Crash Report or Log

https://pastebin.com/AFkKpL0T

Operating System

Windows

Mod Version

0.5.1d

Minecraft Version

1.18.2

Forge Version

40.2.4, 40.2.10

Other Mods

Double Slabs 5.0.0

https://www.curseforge.com/minecraft/mc-mods/double-slabs

Additional Context

No response

[ToastVerbot]

Crash report as a file:
crash-2023-07-30_12.27.08-client.txt

Log-file:
2023-07-30-6.log