It doesn't really freeze, on selecting an option, the selc_window deactivates. In your code, add this at the end:
"selc_window.activate();" without the quotation marks
Try using the https://synrec.itch.io/rpg-maker-mz-preloader plugin I have here, it should be possible to load fonts into the game using that
The steam version should have the v1.4 soon, as for English descriptions, is your RPG Maker in English? It should have English and Japanese display options.
The script call: $gameTemp.closeMenu() will close the existing menu whilst $gameTemp.openMenu(identifier) will open the menu.
identifier is the Menu settings identifier from the plugin parameters and must be in quotation: " "