To target visitors from the EU, you should use this function within the function that determines where the visitors come from (Composite.Web.Html.CountrySpecificContent)
Please see http://docs.composite.net/EU-Cookie-Warning
On the other hand, if Composite.Web.Html.AcceptAlert by itself shows no alert, please make sure that you haven't already (accidentally) "accepted" it. If the cookie has been added in your browser, the alert will not pop up for you in that browser.
UPD: Just tested it (v. 1.0.3) on Composite C1 4.2 Update 1, deployed locally (both as localhost and with a fake domain name set via the hosts). Everything is working as expected.
On the first access to the website, an alert does appear at the bottom of the page. After I've clicked the OK button (accepted it), the alert no longer pops up. To re-test it, you need to remove the cookie already stored for your website in the browser's cookie storage (or use a different - not yet used - browser).
Please see http://docs.composite.net/EU-Cookie-Warning
On the other hand, if Composite.Web.Html.AcceptAlert by itself shows no alert, please make sure that you haven't already (accidentally) "accepted" it. If the cookie has been added in your browser, the alert will not pop up for you in that browser.
UPD: Just tested it (v. 1.0.3) on Composite C1 4.2 Update 1, deployed locally (both as localhost and with a fake domain name set via the hosts). Everything is working as expected.
On the first access to the website, an alert does appear at the bottom of the page. After I've clicked the OK button (accepted it), the alert no longer pops up. To re-test it, you need to remove the cookie already stored for your website in the browser's cookie storage (or use a different - not yet used - browser).