I posted this to the discord but im reposting here in case someone has the same problem.
the mod is missing the </StringTableList> tag at the end. If you have notepad++ (or other software to edit xml) you can edit it to add it. It should look like...
<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<StringTableList
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="../../Schema/Lib/StringTable.xsd">
<!-- Created with the GC4 editor -->
<!-- UnitRaceText.xml -->
<StringTable>
<Label>Race_Robot_Name</Label>
<String>Robots</String>
</StringTable>
<StringTable>
<Label>Race_Robot_Dec</Label>
<String>A species of self replicating robots. Unlike other robotic species, this species can use organic matter to fuel a replication factory that will generate new entities.</String>
</StringTable>
</StringTableList>
If you can't edit it I uploaded a copy to the modding channel of the discord that has the closing tag added. It's really common in anything to do with computers to forget to close things (eg forgetting a semi colon in java). so until the file is updated on the workshop just replace that file with the one in the discord.
Also, by race do you mean citizen? or faction? because the mod hasn't defined a new faction, just a new citizen. so you'll have to create a new faction and under the abilities tab click the 3 dots beside "citizens" and the robots show up there
