I still say you guys are all missing the main point with triggered free actions. They happen on step 5 of the attack which triggered them (or earlier in some cases). Thus they happen before the charge has ended and there is no action restriction in place at that point in time. So if a barb charges, hits, downs the enemy, gets another action due to that etc, then those are resolved and are perfectly legal, as would anything triggered by them in turn be legal. Once all triggered actions are done, step 5 of the charge completes and thats it, you can't do anything more except burn an AP (which is obviously a straightforward except to "no more actions" I mean come on, stop abusing English).
This satisfies everyone. Nobody gets rooked out of a triggered action, and you can't expend actions once the charge is done, even free ones. It is 100% compatible with RAW and works fine.