Importing Lightroom Albums into Adobe Portfolio sequence of photos change

How do you prevent the order of photos from changing when importing Lightroom Albums into Adobe Portfolio?

EX: In Lightroom I have sample pages of an annual report in a specific order starting with the front cover, table of contents, inner pages and ending with the back cover. When I import them into Portfolio the pages become random in order. In Lightroom the Custom Order button at the bottom has been clicked.