EPUB file not displayed correctly

I understand most people reading this forum may not be familiar with writing music scores, but could someone still offer an explanation why most numbers at the bottom of the pages are missing in my epub file? I tried opening the file with a different epub reader, in which it was displayed correctly, so it's clearly an ADE problem. At first, I thought maybe it was a font issue, since the document is using a special music font. But if that were the case, shouldn't ALL numbers be omitted? The attached pdf shows exactly what the epub file should look like. I'm using Windows 10 and ADE 4.5.2.

Any suggestions are greatly appreciated!