crash-2023-02-20_21.21.53-client.txt

Delete this file and try again. C:\Users\Silas\AppData\Roaming.minecraft\config\icbmclassic\explosive_reg.json

If you have not deleted it yet we could use that file to verify why it tried to register missile_module twice.

explosive_reg.txt
I got the same issue and I'm glad to donate my copy of the file

Thanks for the fix, BTW

oh I see what happened, I added a locked ID entry for missile to 24 and your file has that set for mutation. It can be fixed by either letting it regen by deleting the file or changing mutation line to something other than 24.