Apart that a property page is generally fulfilled by unused options/tiles, I add that the content box can be used by a changepage, and I add also that it would be pretty bad if you could get something out from a CE when you're not supposed to.
For example, imagine a CE that represents a very sensible device like a weapon transporter. In the real life, it could be built so that it gets completely destroyed if someone tries to open it using the "brute force" of an explosion: it would be made so that it could be opened only via a specific radio message - and incidentally, it could explode when activated, so that an eventual enemy, standing by, gets killed, and then the "disclosed weapon" would be ready to be picked up.
Of course, this is just my interpretation. I think that Holger has implemented it in this way to allow making the "wall with gem" style of elements in a simple way (no changepages). It has a content, it can be disclosed by an explosion. Quite straight - by the way, I agree with this passage. But I'd prefer the other way round: it has a content, it gets disclosed only if it is set to "can explode" and "by fire". If it is not set to be able to explode, it would simply get destroyed (if not indestructible, of course).
Well, all in all it doesn't make a big difference. If you know how to set a couple of CEs, you can work out the "weapon carrier" without the need to change this particular RnD behaviour, which could even break a lot of stuff. Just wondering about what I'd have expected by such a setting
