Basically twisting vines are treated like ladders, so if they are not touching a wall they become impossible to climb.
EXAMPLE
In vanilla, you stand inside twisting vines and hold [jump] to climb
In GottaClimbFast, you stand inside twisting vines and hold [jump] and you go down as it is registered as a ladder, and need to hold [forward] to climb

The mod fails to load on the latest Forge version due to new requirements to include license info in the mods.toml file. Crash report and example attached.

crash-2020-11-18_13.23.34-fml.txt
mods_toml.txt

A critical error occurred
net.fabricmc.loader.discovery.ModResolutionException: Could not find required mod: gottaclimbfast requires {minecraft @ [1.17-alpha.20.45.a]}

gottaclimbfast-mc20w45a-2.0-fabric.jar

when trying to load with 1.16.4