Simply open the file sct_event_config.lua file in your Scrolling Combat Text folder.
Find:
Code:
[7] = {name="Lightning Shield Faded!", search="Lightning Shield fades", r=0/256, g=0/256, b=256/256, iscrit=1},
Line after, add:
Code:
[8] = {name="Netherwind Focus", search="You gain Netherwind Focus", r=256/256, g=256/256, b=0/256, iscrit=1},
Save, reload your UI, go proc some Netherwind Focus :)