I've been looking at this, and I can't see any problem in the code. Please, try deleting all saved data manually, located here:
C:\Users\yourusername\AppData\Local\Forager_steam\
Launch the game again and let me know if you still have issues.
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FATAL ERROR in
action number 1
of Create Event
for object parEntity:
audio_group_set_gain argument 2 incorrect type (undefined) expecting a Number (YYGF)
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called from - gml_Script_LoadConfigMap (line 27)
called from - gml_Script_LoadConfig (line 52)
called from - gml_Script_Init (line 135)
called from - gml_Room_rmInit_Create (line 1)