egarant,
Does your Heki have the two interior shades on it? Ours has a screen (like a window screen) and a darkening shade that cuts out all the light. Similar to day/night shades, as the darkening shade is pulled across, it replaces the screen and vice-versa. Because we live in the desert, when the camper is not being used, we keep the majority of the darkening shade deployed, but make sure a few inches of the screen section is open to allow heat to escape.
Anyway, we really enjoy our Heki skylight and it sounds like they've been greatly improved from the earlier versions.