Hi will1travis,
Thanks for bringing this up. The ability to save textures from materials is something I personally would love to see in FormIt, too. As an avid user myself, I often need to extract textures from the app and modify them with an external editor, then bring them back in.
This ability is not currently built-in to FormIt, so we'll record your feedback in our system. However, we do have a burgeoning plugin infrastructure and I wrote a plugin that can help you accomplish this in the meantime. This will only work in FormIt for Windows. In the future, we'll have Plugin support for FormIt Web, too.
1. Enable the Script Editor and Script Output panels by going to the Window menu, and checking them both at the bottom:

2. You should now see a new set of panels at the bottom. Ensure you're in the Script Editor window by clicking on the icon with the pencil:

3. Paste the following command into the window, and hit the Play button. Note that you can also highlight the text and hit the Play Selected button (play + cursor/arrow icon) which will only execute the selected text.
FormIt.InstallPlugin("https://formit3d.github.io/FormItWorkflowPlugins/ExtractMaterialTextures");
4. You should now see a panel appear on the right-hand side that looks like this:

As the instructions say, all you have to do from here is select something in the FormIt canvas, like a face or a Group that's painted with a Material, and then click the Extract Texture button. If there's a texture present in the geometry you selected, you'll see it appear in the plugin panel:

Due to security limitations with plugins, we cannot save this texture directly to your machine. Instead, right-click the image in the panel, and click "Copy Image." Then use Photoshop or Paint (many other apps work too) to paste the data from your clipboard, then save the image in the location and format of your choosing.
Note that the plugin panel is persistent, so it will always appear when you start FormIt for Windows. This can be helpful if you often need to extract texture data, plus it doesn't take up much screen real estate. You can always close the plugin per-session by clicking the little "x" in the corner, or you can permanently uninstall it similarly to how you installed it using the Script Editor panel. Paste the following in, select the text, and hit the Play Selected button:
FormIt.UninstallPlugin("https://formit3d.github.io/FormItWorkflowPlugins/ExtractMaterialTextures");
I hope this helps. I'm using this plugin myself until we build a way to do this directly from the app. I've built a few other useful plugins, and we're planning to release a better way to install/uninstall them in the future. For now, they can provide useful workarounds like this.
Regards,
Josh Goldstein
Senior Product Manager