Hello @Aris_ ,
To clarify some things first, the option you unchecked in the configuration is not used to enable or disable CanFD, but to select the protocol it's using (ISO CanFD or non-iso CanFD):
robertv_0-1742555084252.png
In terms of sending normal Can frames (not FD), that should be achieved by simply opening the Can_Write block and unchecking the "Can FD Message" option, which you can see here:
robertv_1-1742555157815.png
Let me know if this helps and you start seeing the Can frames on your Kvaser Leaf Light v2.
Regards,
Robert V