From the three examples, I'm 100% with you that the power torque system wasn't the best moment from Campag. Hence they've stepped from it completly by now. Then again, the tool you're referring to isn't a Campag tool (as they actually never had one) The Cyclus Tools worked very good for me for instance.
Until the introduction of the 13s chain, Campagnolo never had a quick link, only the traditional pinning and peening. So if you're trying to make an i.e. KMC quick link work with something that's not designed to work based on that closure system, it might lead to a less than perfect result together with some frustration whilst trying.
If the Campag ergopowers require a torx key instead of allen key, you simply need to purchase a torx in the right size. There's a reason it's a torx instead of allen and it's not to make the life of the home mechanic more difficult than need be. ;)
Please don't get me wrong, I'm not trying to point a finger but simply trying to put things into perspective. I work in the cycling industry myself and from experience I know it's very, very difficult to provide the correct information / availability to all the different channels.
People will always try combinations / solutions that are not desigend for each other with possible frustration and disappoint as a result.
I'm not saying the Campag way is always the right way to do something but I do believe (no matter the brand) it's important to make sure you're using the right tools and spare parts for the job.