Thank you, jims@jims, Piggy1, wocmultimedia for the tips to make it works while the plugin author is (I hope) working on the official update.
I have concern here regarding new WP feature of “auto update” the core files. I don’t want to encounter this problem everytime wordpress auto updating core files. Could this plugin author think some ways to make us (non-developer) to not deal with the same problem on every wp update, please?