I'm trying to change the VTweaks config file to modify behaviour and when I make changes in the file directly and then start Minecraft it doesn't read the changes I have made. When I make changes in the config GUI these work but are not written to file. The changes made in the GUI stay even after closing Minecraft and opening it again implying these are being written to a file somewhere just evidently not the on in the config folder I am editing.

I'm trying to change the challenger mod blacklist but will need to use the config file to do this as once I have worked out how to I need to do it on a server.

My config file had got broken somehow (possibly a config from an old version or something) and so had multiple blacklists in the same file...

All fixed now! (I just moved the old config file and updated the auto generated one.)