Seems like the "Approve All" buttons on the "My Changes" dashboard seems to be no longer available, although it's still referred to in the help. Is this a defect or is there a new way to approve all of the outstanding items?
I can see that this has been escalated, but I'm not sure if it has been resolved for you - if not, could you clarify if you are referring to process/doc/changes or actual process approvals?
The 'mark all as seen' option is reliant on a site configuration setting being turned on - if someone has turned this option OFF in config the option within your dashboard will no longer show.
This button will also disappear if you only have changes that require action from you rather than simply marking as seen.
Does that help at all?