#7, a 47-story building was not "shielded by WTC 5 and 6", because those were only 9 or 10-story buildings (which did not utterly collapse because, being long low structures, there wasn't enough weight pressing down from above to cause them to. But they were pretty much completely destroyed anyway because the debris punched gigantic holes through them from ceiling to sub-basements, and then commenced the buildings burning).
Remember the debris formed an umbrella shape as the tower fell? Very easy to reach #7 across the narrow street separating it from the plaza. If you see an overhead diagram of the complex, you will see that #7 was trapezoid-shaped. The debris pretty much took off one lower corner of the building on the short side of the trapezoid. Meaning that gravity was working on all the floors above it (more than were above the strike zone in Tower 2), without enough support to counteract. This is why it eventually collapsed bottom-up, instead of top-down like the towers. The damage was at the bottom of the building not the top.
Faulty premise #2.
There were not "minor fires on two floors". There were huge fires and they burned for hours. Firemen were never sent into #7 because the building was making funny structural noises from the get-go, and they were pretty sure it was coming down. It wasn't worth the risk, so they let it burn.
I confess I don't understand the significance of the squibs or why you guys focus on them so. Smoke goes up. If a smoky building collapses, it's going to expell the smoke through any openings on its way down. You expect the "squibs" to look like they're racing DOWN a falling building or something? I really don't get it.