I fixed the error in a separate GitHub fork. Added IR2 assembling-machine "steel-cleaner" to exclusions in config.lua.
<Redacted>
Needs to be extracted, added to new .zip nested under a "Squeak Through" base folder, named "Squeak Through_1.8.1.zip" exactly, and put in mods folder and enabled in mod-list.json.
Edit: Uploaded a Drive link w/ the correctly formatted file here <Redacted>. Don't expect it to be up for long.
Edit 2: Since the fix has officially been integrated into the latest version, links have been removed.