Build and Shoot

Hi guys I need help with slab6, my keyboard is international and the INSERT key doesn't work.
I have tried pressing all keyboard keys and none adds a new voxel/cube.

Please can someone help me I need to change this key to another in my keyboard

From what I can infer, you are probably using a laptop, or a keyboard with dedicated, multi-use function keys. You will need to either hit the "Fn" (function) key every time you wish to hit the INSERT key, or you will have to configure an option in your system's UEFI to disable it. Common names for the option include "action keys", "hotkeys"; if you Google your laptop/motherboard's model, there should be a manual available for reference.