This is tedious, but finally I got this to work as described. It is a pity that Microsoft does not add a function to do this in a more straightforward and intuitive way, maybe on the [Format Picture] dialog box.
I would add that the default [Properties] in the [Format Graphic] dialog is "Move, but don't size with cells" - I changed this to "Move and size with cells" - since I was using symbols in the header row. On the other hand, if (say) a picture of a person in a directory spreadsheet was important, it may be best to expand the cell to fit the picture (presumably sized at the outset to some standard size).
Also, I notice that when an image or icon is selected, the [Alignment] tab on the [Home] ribbon is dimmed-out. It would be nice to be able to align left, centre or right. For example.
I also tried this with:
I dragged the selected icon to the desired cell, then snapped the edges to of the icon to the cell borders - while holding down the [Alt] key. This left me with a distorted icon ratio.
Then, in the (right-click) {Format Graphic] dialog box (expand [Size]) I de-selected "Lock aspect ration" then manually changed the width (or height, as appropriate). However, before I did that, I calculated the height to width ratio of the original icon, and used that ratio to determine the appropiate width (or height) to enter.
Having done that, there appears to be no way to centre the resized icon within the cell. It defaults to left alignment when, I suspect most folks would prefer it to default to centre alignment. The only way is to manually move the icon using repeated [right arrow] clicks. This is, again, tedious.
Surely the Microsoft office team could embed a function to automate this in the [Format Graphic] / [Size and Properties…] - it seems both lead to [Format Graphic].
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