Hello,
Do you see any exceptions in logs or error in the browser when you open site pages?
Check the paths of pages that fail with crx/explorer Access Control Editor.
1. Browse to the failing Page's path
2. Open AccessControl there.
3. Select Test on the very bottom of the AccessControl Editor window
4. Browse your Principal
5. Check include Group Membership
6. Check all JCR Actions
7. Check Repository Level
8. Check Effective Policy
9. Submit
Remember the JCR actions for Node that are false.
Repeat for Page's jcr:content Node's Path
Now check on any of the actions that are listed as false and compare it with the working user permissions.
Regards,
Vishu