I'm pretty new to it myself and it took quite a bit of experimenting for me. I use center justify and after inserting a picture I hit enter and then insert text or another picture, That way the pictures are in a vertical line. I then go through the pictures and right click on one which gives me some kind of option near the bottom that lets me resize the picture.
I'm sure there are smoother ways to do it but I have even used this method to use my regular 16 pictures and then had what extra ones I need. You can choose to add all your pictures in the description if you want.
In my photo editing program, I've combine 5 different views in an album page and made one image out of it for faster loading. I had one very nice auction that my 16 pictures each had five different pictures in each and had very good comments and results with that auction.
I'm still playing with different ways with the pictures so maybe someone with more experience can simplify it for you.
Good luck.