Hi, I had a good opportunity to make a simple book with Publisher, and have noticed that the picture frame tool could definitely use some improvements. First, it is too difficult to modify the scale or position of the image inside of the frame. i often have to click a different tool, re-select the picture frame tool, then click on empty space, then click inside of the frame I want to edit. Could scaling/positioning the image be done with the direct selection tool instead? The rotate icon that comes up is also extremely difficult to use, the radius to turn the image is too small, and it typically ends up rotating all over the place/way past the angle I am trying to achieve. The mini window that comes up when you want to position or scale an image is great.. except I could never get it to work properly. You should be able to use this window for resizing OR by dragging the corners of the inner image to line up where you need them. I often found myself clicking out/in/switching tools a ton just to scale the inner image. Maybe the little scale/position window that pops up can have a button to "activate" the image inside the frame, sort of like the weird doughnut thing in adobe when you hover over a placed image. Also, not sure if this is a bug or not, but whenever you adjust the frame around an image after scaling/positioning it, it immediately snaps back to its default location/scale. Which is really annoying. I'm also not sure if this is Publisher trying to determine the correct orientation of images once I place them into a frame or just a bug, but 90% of the time it would import an image and then rotate it 90/180 degrees automatically. It's pretty annoying, I had to rotate the vast majority of images as they loaded in rotated (didn't seem to be a trend with this; I inserted images that were a variety of proportions and orientations, and the rotate that Publisher performed on them seemed very random).
Speaking of placed images... It's really confusing that placing an image isn't the same as having an image inside of a frame. And it's annoying that images inside picture frames, by default, come in embedded instead of linked. I didn't see any options for adding a picture frame image and having linked be the default option. I only knew that the images weren't linked when a notification came up to tell me that the file was getting enormous because no images were linked.
It's also too hard to find the files that you have linked into your document. I think having those be available to view in the tabs next to the pages and assets tab would be very helpful.