The game gives the following error after failing to load mods:

java.lang.NoClassDefFoundError: net/neoforged/neoforge/network/NetworkRegistry$ChannelBuilder

My guess is that it's caused by the Network rework made in Neoforge version 20.4.70-beta as the game fails to load in that version and the versions after it but starts with no issues in the 20.4.69-beta version.

Here is the full log: https://mclo.gs/uIM5hDE

Fixed by 8b3fad1. Will release a new version shortly.