Again, it's a strange mix of parts but it will work with friction shifters.
There should be no problem with the chain getting wedged between chainrings. This is largely myth, and useful myth (for corporations) because it makes people think that they need to upgrade their cranks. I've used 9-speed chains with cranksets from old 10-speed bikes (that had 5 freewheel cogs and fat chains). No problem.
As for the chain fitting in the rear derailler's cage, just use a standard 8-speed or lower chain (e.g., SRAM 48 or 58). Works with everything from 8 speed and less, should be narrow enough to work with the rear derailler.
That said, it's sort of a waste that you're using such high-end and current Campy front and rear deraillers. Unless your goal is to use all Campy stuff, I'd put the front and rear deraillers on eBay and use other deraillers. Alternately, you could keep the deraillers and crank and upgrade to 10-speed Campy shifters and new rear hub eventually.