The original files were named in the correct order, like Angels_Rest_1, Angels_Rest_2, ..., Angels_Rest_9, Angels_Rest_10, Angels_Rest_11 and so on -- but the gallery software can't actually count, it just sorts in ASCIIbetical order. So you get page 1 first, then 10-16, then 2-9. (The database enforces the input sort order, so if you download, you get filenames like 01_Angels_Rest_1.jpg, 02_Angels_Rest_10.jpg, et c.)
Base +8, Anonyslime +7, BlueRingedOctopus +4, dbf1ofmany +2, dismas +7