Forum adverts like this one are shown to any user who is not logged in. Join us by filling out a tiny 3 field form and you will get your own, free, dakka user account which gives a good range of benefits to you: No adverts like this in the forums anymore. Times and dates in your local timezone. Full tracking of what you have read so you can skip to your first unread post, easily see what has changed since you last logged in, and easily see what is new at a glance. Email notifications for threads you want to watch closely. Being a part of the oldest wargaming community on the net. If you are already a member then feel free to login now.

So if you have a mek with a kff inside a stompa, say with a unit of meganobz or whatever, and your sweet new ride gets trashed by a lucky 6+6 from a D weapon, what happens to the guys inside. Do they get the KFF invun saves? Is the explosion a shooting attack, Im inclined to say yes, as its fire and shrapnel shooting everywhere, but then part of it is collapsing on you also. Should it be treated any different then say if your battlewagon explodes?

Sadly no, for a couple reasons.
First and foremost when a model with a KFF is embarked on a transport, the models inside don't benefit from the KFF. Only the vehicle does.
Second, no saves may be taken against a 6 on a destroyer result.

The unit inside isn't suffering the D hit that is destroying the Stompa. My interpretation is that the unit inside would get the KFF save against the explosion caused by the Stompa being destroyed. Unless of course the centre of the resulting blast hit the unit and got a 6 result as well.

Iirc it's in the wording of KFF that it doesn't protect you from explosions.

You are remembering correct. While embarked, the KFF does not protect anything but the transport it's embarked on. Since a unit takes explosion hits first and then disembarks, the KFF would not be able to protect anything from the explosion.