Plugin conflict

Hmm, there is a js error saying ‘TypeError: gapi.plusone is undefined’.
How did you add the sharing buttons?

Oops, that’s a payed one…
Luckily I was able to reproduce the issue with the free version of the plugin (https://wordpress.org/plugins/wp-image-hover-lite).

Google+: I discovered an issue in the jquery sharrre plugin (part of image hover showcase). Sharrre is checking if a google javascript api is present, and if not it will load it. In fact a google API is there (loaded by he recaptcha plugin), but only the recaptcha part, not the plusone part. That’s where the JS error comes from.
This should clearly be fixed in the sharrre code (it should explicitly require plusone to be present) on https://github.com/Julienh/Sharrre

Digg, delicious and stumbleupon simply don’t work because of the js error. (The script stops execution after the error)

You should be able to manually fix this by loading the script //apis.google.com/js/plusone.js somewhere in your theme header.
Somewhat hacky, but maybe helpful…