It appears that Joomla 3.5 has broken ALFContact's reCAPTCHA support.
Working on a solution, in the mean time stick with 3.4.8 if you badly need the reCAPTCHA feature.
ALFContact v3.2.0 is officially released now.
In this latest version the built-in reCaptcha has been replaced by support for Joomla's reCaptcha v2 plugin.
The possibility to add Bcc's for each contact has been added as well as a fix for the maximum number of characters for the message.
I hope you enjoy this new release!
As always, only once you release your software bugs are discovered ;-)
And so apparently we had a small bug with the ReCaptcha support which has now been fixed in v3.2.1
Also it's june now, over 6 months since support for Joomla 2.5 has ended so also support for ALFContact v2.0.8 will end.
It's been quite for a while now, but don't worry, ALFContact is still under development ;-)
At the moment I'm testing 3.2.0. for the Joomla 3 series.
This version will include support for Bcc: and the new Google reCaptcha: