At first I disabled caching of Urls.
Later with subsequent releases it seems that the problem has been resolved.
However in my website caching of URLs is still disabled

I have a problem with my site,
It seems to me that all the settings are correct,
but on the home-page of my site the title of the site is duplicated.

Here is the URL of the website
http://www.logicaldoc.com/en.html

In attachment I post the screenshots of my settings and Meta Tags of the SEF URL.

Note: the title of the website is: LogicalDOC
I'm using Joomla 3.3.6 and JoomSEF 4.5.3

Well,
after some research and using the empirical evidence and controls,
I found the solution by myself.
In order to add urls to the cache the general management of the cache must be enabled.
So you can enable it from Site -> Global configuration -> System
Change the values in the area Cache Settings (see the image attached)
At the end I can only say that the manual should be a little more explicit on this topic

In my system I can't understand if the cache is working or not.
I've JoomSEF 4.4.0 with Joomla 2.5.8 and Flang 1.2.0
I've enabled the cache as in image_01,
then I've added a lot of sef urls to the cache,
but the control panel tells me that there are no urls in the cache (see image_02).
How can I check if the cache is working?

Thanks for the suggestion,
unfortunately, after having followed the instructions you sent me, the problem is still here.
When i browse a page that has been translated in French, inspecting the source code I can still see the metadata tags description and keywords of the page in english.
It does not matter in the end is not a serious problem...
In my opinion it works best the solution adopted on the 3.9 version of JoomSEF with Joom!Fish, in that case the metadata tags where left empty.
In any case I want to thank you for the support
Alex

I've decided to take another screenshot to evidence the ordering of plugins

Ok, here there are the screenshots of the meta tags and a screencapture of the system plugins.
Thanks in advance :-)

In fact I have the option enabled in the Language tab, but this does not seem to affect the pages in a language other than the default (English).
Anyway I am attaching two screenshots, the Language ​​tab, and Title and Meta Tags tab.
This behavior may have something to do with the settings for the Extensions?
I have this kind of problem because of some plugin on / off of Falang or System related to languages?

On our Joomla 2.5.8 we installed the latest version of JoomSEF 4.3.2 and Falang 1.2.0, and almost everything works fine.
Unfortunately, as regards the meta tags extracted from these pages are only in English.
So when I inspect the source content of a web-page in French I see the meta tags description and keywords of the contents in english.
I must add that I have not specified the description and keywords on the content translated with Falang, and I expected that the velue to these meta tags were automatically calculated as to the content in English (which is the default language).
I would just like to know if there is any option to have automatically calculated the meta tags of the page in language or do I have to manually specify the meta tags for each page in every language of my site.
Thanks in advance
Alex