All this plugin does is add a visual element to an existing feature. I haven't really used the Time Progress Battle System, increasing agility will reduce casting time but it'll also reduce the time between actions.
Err it's a bit clunky but if you literally copy and pasted Window_SkillType, Scene_Skill and rename them both you could probably get the job done. Then just make all my code also refer to the new versions, except for the following:
It's been a weird while. I've been so torn down that even playing video games has been something I avoided. But I shouldn't forget two things. One, I love RPG Maker for a reason. Two, only way to eat an elephant is a bite at a time.