I have WYSIWYG and CKEditor 3.6.6.1 and want to install the latest CKEditor 4.6.1 My goal is to paste images (best if copied from word together with text) directly without uploading them first. 

I got a D7 site with WYSIWYG installed. The module tells me it uses the CKEditor 3.6.6.1 library. In fact, there is no CKEditor module installed, but in the libraries path I see a ckeditor folder. 

I tried to install the module pasteFromWord, and I found it didn't work with my a local copy of my site. So I looked around, and I found there is a newer version of CKeditor (4.6.1) rewritten with lots of features like embedding pictures, and it is open source too. There is only an older version of CKEditor as a Drupal 7 module, and it is driving me nuts to install anything that works.

I read about problems with WYSIWYG and I disabled it, but I cannot uninstall it, so I cancelled the whole directory under modules. I installed the latest Drupal CKEDitor (Dev) but all I see in my text field is htmlcode in full html mode. There are no editor icons. I put higher values for the memory settings in settings.php, restarted the server, cleared the cache, tried all sorts of thing suggested in Why does the Wysiwyg module and Ckeditor library not show the CKEditor when editing a node?

All tests are done as user1. By now, I get a simple text field in plain and filtered HTML mode; in full HTML, the text box body simply vanishes.

In Mozilla the Console gives:
TypeError: a(...).on is not a function
 js_8iXNyfjLJ1tJPju6nAtk8ETos8oLn9Arp0f2Z5uBPaQ.js:850:1412
TypeError: CKEDITOR.dialogCommand is not a constructor
 plugin.js:4:43
in http://localhost:8080/drupal7bis/sites/all/modules/ckeditor/ckeditor/plugins/SimpleImage/plugin.js which is one of the few plugins I enabled so far (nearly all are installed though because indeed I took the full package) and it reads:
CKEDITOR.plugins.add( 'SimpleImage', {
    icons: 'simpleimage',
    init: function( editor ) {
        editor.addCommand( 'simpleimage', new CKEDITOR.dialogCommand( 'simpleimageDialog' ) );
        editor.ui.addButton( 'SimpleImage', {
            label: 'Add a image',
            icons: 'simpleimage',
            command: 'simpleimage'
        });

    CKEDITOR.dialog.add( 'simpleimageDialog', this.path + 'dialogs/simpleimage.js' );
}


});

When I disable this plugin, only the first error remains. The body does not vanish any more in full mode, but still no editor appears.
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As far as I know, you need to use the dev version of the WYSIWYG module in order to use CKEditor 4.x. You also need to grab the 'full build' of CKEditor and not a stripped down one. You do not need the CKEditor module if you are using the WYSIWYG module. WYSIWYG looks for editors in the given paths (usually libraries) - you have to go get it from ckeditor.com.

The second thing you are describing is adding custom or non-core plugins to CKEditor, which is not as straightforward. "Paste from Word" should be available though once you get WYSWIYG and CKEditor 4.x setup in Drupal 7.

I wrote a plugin integration once for CKEditor 4.x under WYSIWYG. I do not recall needing any module other than WYSIWYG and the full CKEditor library for getting WYSIWYG to show up. You shouldn't need any other CKEditor modules. But if you are looking to add other plugins on ckeditor.com - you need to get comfortable with the WYSIWYG API in order to properly integrate it if someone else hasn't done so already.

The reason your CKEditor may not be showing on the edit page is likely due to a JS error - I am going to guess either because you are not using WYSIWYG dev branch, or CKEditor is not the right version, or CKEditor is not installed in the correct path. Please add the error from the browser console to the original question along with any watchdog errors.