I have implemented 5 inline editors on a page using V4, and whilst it's working well in Firefox on my Mac there are problems in Chrome and Safari (haven't even started on Explorer yet).
The page loads with 5 div elements each with content editable set to true and a different id in the HTML. At any one time 4 of these elements will be hidden and one visible, this is controlled by Javascript. The first element is editable but the following 4 won't edit. They allow the element to be clicked and the CK editor toolbar appears but all the buttons are greyed out. There is no cursor showing but text can be selected and the copy button in the editor toolbar becomes useable, nothing else is possible.
In the developer panel in Chrome the 4 elements that won't edit are set to contenteditable false contrary to the HTML. I can change this in the developer console and all is fine. Safari seems to think they are still editable.
Any thoughts appreciated.

As always a bit more work and
As always a bit more work and the problem starts to become clearer. Hiding the elements eems to be the problem. If they arent hidden then the editor works. I am hiding them initially using a CSS class. It looks like this needs a new approach, will keep this thread updated.
Basically you're dealing
Basically you're dealing with what is a loooooong legacy of crap support in browsers for the contenteditable attribute. Check out some of those issues in google. contenteditable="true|false" actually has nothing to do with CKE - it is a standard supported capability, and even with CKE completely gone, you would be able to type in those div's that are set to be editable. CKE and other WYSIWYG editors like it provide a macro interface on top of that that allows you to make changes to the DOM within those editable div's, etc. - but the problem you are seeing would be the same with or without CKE in the mix. Unfortunately, all of the solutions I have seen posted in various forums about that problem are hacks that are hit-or-miss at best, and it is possible that you might not be able to reliably fix it at all as it is a browser support issue.
I have the same issue
I think the analysis by skelly is right, but still it would be nice to know whether anyone has discovered a work around that even half works. It is a frustrating problem because everything else about CK4 is working well. The inline eidting is great and makes the user interface really sweet.
Thanks for the input. Fixed
Thanks for the input. Fixed this with a bit of a hack by not hiding the elements on loadining and putting a big grey box over the whole screen with a .gif progress bar. Then loaded a javascript at the end of the page which waits 5 seconds then hides the grey box and the elments with inline editors I don't want displayed. The editor elements can then be shown and hidden with Javascript and the editors work well. This works on Safari, Chrome and Firefox on Macs, next Explorer.
Fixed?
Does anyone know if this issue has been fixed? I'm having a similar problem but I'm not sure if it's my code or the browser (IE)