This article contains a detailed guide on how to find out the version number for each mscrm-addons product in CRM 4.0.

Location of the Language Settings on the Client & Server

The name of the Language XML File is: .XML

SSL enables browsers to communicate with a web-server over a secure channel that prevents eavesdropping, tampering and message forgery.  You should always use SSL for login pages where users are entering usernames/passwords, as well as for all other sensitive pages on sites (for example: account pages that show financial or personal information).

Configuring SSL on Windows with previous versions of IIS has been a pain.  Figuring out how to install and manage a certificate, and then associate it with a web-site, is something I bet most web developers don't know how to enable.

CTI does need the server component in a hosted environment as well, but you can launch the CTI Server setup from any Client, as long as you have a user with full access to CRM.

You need to select the hosted options on the Connection dialog. 

Basics:

License-checks are done each time the application is accessed by a user.

Having an invalid license stops the whole product from working.

An invalid license will never have any impact on Dynamics 365, it only limits the addon itself.