Written in reference to latest OS 10.11.6, El Capitan with iCloud Drive activated, there is currently still a bug which crashes Finder whenever attempts are made to access e.g. iCloud Pages folder in Finder.
To cure this bug, log into your iCloud account via an internet browser and access the iCloud application which causes your Finder crash.
For example if attempts to open your iCloud Pages folder in OS X results in Finder crashing, then access the iCloud Pages application on your internet browser.
A listing of all existing files should be displayed.
Check whether any of the files ar currently being shared*.
This is indicated by a green triangle on the top right of the file icon:
Click on the green corner and in the pop up window that follows, click Stop Sharing.
Do this for all files that are shared.
Turning off file sharing may take some time to take effect, so a bit of patience is required until the pop up window confirms file sharing has been disabled.
Your OS X Finder should not crash anymore and you can once again access your iCloud folders without this inconvenience.
*files become shared when you right click the file and select the “Collaborate” option
For a permanent fix in the future please join us in submitting your feedback to Apple regarding this issue at Apple’s Feedback page.