Make sure that CET works fine without any mods installed.
Make sure the mod that you are installing is compatible with the latest CET.
You need to bind a hotkey in the Hotkeys tab of the CET overlay. Check how-to here.
The hotkeys only work when the CET overlay is closed.
You need to press the hotkey combination in the right order.
Ctrl + Shift + S is different from
Shift + Ctrl + S
You need to open the CET overlay to interact with anything using your mouse.
You need to change the default font of CET in order for the characters to show properly. You can follow this guide here.
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