how do I Edit>Transform>Skew a selection in a Smart Object?

OK, here's how I would have done it! I start with the object I intend to place being saved in the PSB file format (Large File Format). At this point, smart objects are not involved. I place it in Photoshop using the path: topmenubar-file-placelinked. Photoshop converts it into a smart object inside the file you are placing it in as you do this. The original file remains on disk as a PSB, it does not become a smart object itself. When I want to alter its appearance in my final file, I double click its icon in the layers palette and the PSB opens up, where I can edit it to my hearts delight. In the case of bartonlews file, I would have duplicated the main layer in the (now saved as a) PSB file with NO smart objects within it, then on that new layer I would select and mask to reveal only the tiles area he wants to adjust. Then I would delete the mask, or confirm that the mask is locked to to that image on that layer, and then transform this new tiles layer (I would probably use distort, so I could raise the left corner only) and then save and close. If my layer includes transparency and the sub layers are showing behind, I turn off visibility of the sub layers, then save. The smart object should auto update in the file where you started, but if it doesn't, you can force it to update using the properties panel. Most of my placed linked SO PSB objects contain multiple layers, masks, and separate versions on their own layers. I disagree with a previous commenter who said you can't use smart objects with transform-again, and that you have to rasterize the layer before it would work (paraphrased). Rather I contend that making transform-again work is a tricky process, and you have to follow a very specific set of steps to engage it, and I still don't have it totally wired! I have managed to make it work intermittently, but somehow, not consistently. Various web tutorials on this (and there don't seem to be many) offer different keyboard combos to invoke it, so it is a bit confusing. I haven't found anything of note at Adobe's site either. When I feel rock solid on it, I'll post an update on what is working for me.  The jpg below shows both versions (layers) of a single PSB file, and the final PSD files they were placed in. I would NEVER have attempted to build these files WITHOUT transform-again, it would have been painfully slow and tedious. The beauty of using smart objects in this way is that when I wish to change the appearance of the object inside my final PSD file, I can double click on the SO icon in ANY ONE of the layers it exists on (when using transform-again, each placed iteration lands on it's own layer) and when the PSB opens, I alter it, and save it, and when I return to my original file, every iteration updates automatically, nearly before you can switch tabs to go back to it! I know this because I was watching, hoping to see the update take place and missed it! Each iteration can be transformed differently than the others within your final file if you wish, i.e. warped, scaled, rotated, skewed, etc. Regardless of those differently appearing iterations, when you update the PSB file, all the interior contents of the iterations update, while maintaining their own unique transformations. Additionally, you can relink some of the iterations to a DIFFERENT PSB file if you want to. There are a total of three images used in my samples, one is the pen nib shown in the jpg image, the second is a colorized shere, and kudos to anyone who can figure out what the third image is!