https://sims4studio.com/thread/606/editing-shadows?page=1

My Wife wrote this for me because I was having trouble explaining it, so was she. Its a lot easier than it looks.

So you've just edited your mesh and your all excited to see your mesh edit. You load up the game and see this.

The cause of this is the shadow file. When you make an adjustment to a mesh it does not alter the original shadow image. You must manually do this yourself. The following is a tutorial showing you how to edit your shadow image.

First step is to open the package of your edited skirt mesh. In this example my package is called shadowskirt. In studio click on the warehouse tab. In the warehouse tab you will see a list on the left. We will be clicking on RLE2.

Now you may have a few RLE2 click on each untill you see something similar to the image below

Next we want to click the export button below the preview image. When you click the export button it will prompt you to save the file. Be sure to save it where you can find it. For this tutorial I'm going to call mine shadow. Now before we jump into editing it. We also need to export our edited texture. Go back to the studio tab and export your texture, saving it somewhere you can find it easily. For this tutorial I'm going to call mine texture.

Next step is to open the texture and shadow file in your photo editing program.

The simplest way to fix your shadow issues would be to simply erase the bottom line of the shadow. But if you wish to keep some more detail in your skirt mesh edit you can use the following method.

If you wanted to edit the shadow the easy way rememebr not only do you have to erase the bottom line in the layers part of photoshop,but you also have to click over to the channels tab and erase it off the alpha channel too.

Below is a picture of the layers and channels tab.

Now we will proceed and show you how to keep the shadow detail on your mesh edit.

The first thing we will do is go to both the texture and shadow files channels tab. We will then click on the alpha channel.