The games is quite addictive and I am stuck on level 30, after that it was time for a break. Since there is no password, so remember to keep the tab open in your browser.
The instructions shown in the image are rather clear, use you mouse to move the warthog, control the grenade pile placement and amount of grenades. Click the button to explode the grenades and restart the level in case you miss. The yellow arrow takes you to the next level.