These instructions will work for either a server or single player. But if on a server, make sure to upload the file to the correct place on the server, and when "restarting" the game, restart both the client and the server.
1. Open StarMade. Go to "Tools & Mods," and open the Block Editor.
2. In the block editor, go to the "Recipes" tab, and add a recipe for the Micro Assembler.
3. Click on "File", then "Save As..". Browse to the "customBlockConfig" folder and save the file as "BlockConfigImport.xml"
4. Restart the game to ensure the new xml file is loaded. (I noticed that changes to the config file did not always hold when I did not restart the game)
5. Start a single player world. Place down a micro-assembler, and look for the recipe. It won't be there. Also try to put the items in to perform the recipe, and it won't work.
Now, let's make it work, at least till the next update.
6. Open up an explorer window and browse to your "StarMade/customBlockConfig/" folder. Rename the file "BlockConfigImport.xml" to "BlockConfig.xml". Cut this file, then browse to your "StarMade/data/config/" folder. Rename the original "BlockConfig.xml" to "BlockConfig.xml.orig". Then paste the cut file.
7. Restart your game completely.
8. Start the game and start a single player world. Place down a micro-assembler. Open up the "View Production Recipe" tab and you will now see the custom recipe. It should also work. However, since the "BlockConfig.xml" file has to be changed, then every update this file will be replaced by the updater, which is no good for servers.