Issues with ckeditor

[temi]

1. insertion of special characters from the toolbar no longer working as expected. Mostly this seems to be that the special characters are inserted at the start of the sentence/paragraph and not at the current cursor location.
2. formatting highlighted text is not working via the toolbar icons. Example, when you highlight a section of text and click the bold, italic etc. icons, nothing happens.
3. copying and pasting within a field no longer works properly and the selected text is not placed where directed by the cursor but instead the cursor jumps about and the selected text is usually inserted earlier in the paragraph creating an error.
4. The undo function is playing up (i.e. does not work, takes several attempts, or creates a new error) when trying to undo the previous edit, which is often used to correct an error.