I've been struggling to get collective.captchacontactinfo to work on a Plone 5.0.8 site and have contacted the good folks at Red Turtle Technology via email for help.
But while I wait, I'm curious if ① anyone has had better luck than me (and what's your secret?!) or ② there are some other CAPTCHA solutions to the contact-info page that I've overlooked.
It would be helpfull if you could provide a bit more information than ‘it does not work’. What did you do to install it, what is happening (or not that you’s expect), and which version of the add’on are you using?
Well, I was just asking if anyone had success, not necessarily to report details of my own lack of it. But if you insist 
Plone-5.0.8
collective.recaptcha-2.1.0
collective.captchacontactinfo-2.0.3
norecaptcha-0.3.0
The public & secret keys are installed and I can confirm that collective.captchacontactinfo's own contact-info is being called by modifying the templates/contact-info.pt and inserting some sentinel HTML which does indeed appear. What doesn't appear is the CAPTCHA widget.
Inserting a PDB breakpoint in the "updateFields" function of the ContactInfoPolicy class shows that it's never called for some reason.
Happy Thanksgiving for those who celebrate it!
Hi, we (RedTurtle folks) are using it on several Plone 5.1 sites.
I tried on a fresh 5.1 installation and it works, but on a 5.0.8 seems not working as you reported (i've never tried it on <5.1 versions).
We should update the classifiers for sure, but please open an issue on github and we will try to fix it
Thanks, cekk.