There seems to be some typos/ other errors. Here's how to fix them.
To fix the nurse:
- in factions/usa/units/nurse/nurse.xml, delete the line:
To fix the sniper:
- in factions/usa/units/sniper/sniper.xml, delete the line:
- in factions/usa/usa.xml, remove the line:
<unit name="sniper_" amount="0"/>
The version in the mod center should be updated with these changes. That being said, I have other questions about this faction...