Well, MSP isn't meant to work like that for single image files, personally i think for good reason.
Page order is meant for multiple pages in one file. You can set custom page order for each file in a song. Your images are files with one page each to MSP though. Either you Import the Images as multiple single files in a song and order them manually (or take snapshots directly with the camera) or you convert the images to a multiple page PDF with Adobe Acrobat or one of many other tools and import that. Then you have all the benefits of page order and so on.
After all MSP basically is a PDF reader though it also supports image files.
P.S. And also there are lots of apps for scanning/photographing to convert your scans directly to PDF on your Android phone or tablet which you could consider.
Page order is meant for multiple pages in one file. You can set custom page order for each file in a song. Your images are files with one page each to MSP though. Either you Import the Images as multiple single files in a song and order them manually (or take snapshots directly with the camera) or you convert the images to a multiple page PDF with Adobe Acrobat or one of many other tools and import that. Then you have all the benefits of page order and so on.
After all MSP basically is a PDF reader though it also supports image files.
P.S. And also there are lots of apps for scanning/photographing to convert your scans directly to PDF on your Android phone or tablet which you could consider.