Can you check using /ver MundoSK that your version is 1.7.5-BETA.7.154? All of that worked when I tested it and I've had similar issues with GitHub in the past, you can try this link instead if it turns out that was a different version: https://github.com/MundoSK/MundoSK/blob/temp/MundoSK.jar.Thanks for the update. I think this broke some things... Here's a couple photos
The last error also happens with this code:
code_language.skript:on packet event play_server_spawn_entity_living: broadcast "%""uuid"" pinfo 1 of event-packet%"