Sharepoint setup with approval process and template file

PSCIT If I understand.. you have a locked template file that users can fill out, but not edit the template. Every time the template is opened it should be a new form.  You have two questions - 1 how to get the form to open as a blank every time, and 2 how to send a link to the form (content type).

1 - Add the document as a content type.  Click on the menu > Add Template > and upload your file.  When you are done you can edit the menu to remove the other items if you want. 

Now the default document can be your new Custom form. Every time someone clicks on it, a new instance of the form will open.

2 - Send a link to the new form...  I don't know!  Maybe someone else will have the answer.  You could send them a link to the SharePoint library and have them just click on new and select the form they need.