Crushing Fist issues

I recently started playing a retaliation build using Crushing Fist and it seems a bug that has been in for a while is still happening.

During Mapping the Skill will star the Animation, a fist will form, then it will vanish. No damage is done and the Cool down has been reset/unable to recast.

There are also instance of the skill not working if the block trigger is being reset very fast. Spamming the corresponding key will not have any effect on the skill being used. (in my instance it is on the Space bar).

Character: Freakblocks
Gem level: Currently 18 (but has been an issue from level 1)
Gem links: Crushing fist - Fortify - Fist of war - Pulverise
Socketed into a Devoto's Devotion.