I am experiencing the same error on different computers. I have just reinstalled Evernote in a recently adquired laptop and the strange cursor behaviour also happens on it. When you have a selected text and copy it, the selection dissapears and you go to the destination program with the previous copy-paste content on the memory. Plus when you are going to write, the cursor dissapears and you need to click again.
If this would have happen when I began to use Evernote, I'd never have used for my work. Hope it can be fixed soon. It's really very annoying.