Very nice. I've enjoyed sorting my Portuguese/Colonies stamps over the years, especially the omnibus issues.
The stamps on some of the pages show quite a bit of staining, that appears to be from the acid in the paper reacting with trace moisture -- it's not unusual to see this in the older Portuguese stamps, especially if they have been stored in environments elevated temperatures/humidity.
Although it's not contagious like mildew, it can still promote acid attacks on nearby stamps/pages. So you need to remove them from the pages and isolate them. The acid damage is not reversible, and unfortunately, will take off a pretty huge chunk of the retail value. There was a reason why you were able to purchase the lot so cheaply.
Thanks for sharing the pics! I enjoyed looking at the stamps!

k