You should be able to open up the kinds.svg file in a text editor and you’ll see chunks of text in .xml format. In skimming through it you’ll notice there are chucks of “code” for each of the respective kinds. You should be able to open up the beer.svg file and cut and paste in the appropriate code for the beer icon into the kinds.svg file. (You may have to tweak small parts so that it follows the format of the rest of kinds which you can use as examples.) Doing a version bump of the plugin will force WordPress’ admin cache to flush and cause the plugin to display the new icon. Otherwise, you can usually wait a few days and it should auto-flush and show the icon(s) you expect. If you’re hard-pressed, let me know and I’ll try to generate one for you.