Those are some of the uptown files, and they are probably either corrupted or missing.
The easiest way to deal with this is to verify the integrity of the game cache on steam. To do this, you want to start by going into your steam library. Right click on hawken in the list of games on the left, and then click properties. In the properties window, open the local files tab. You should have the option to verify the integrity of the game cache once there.
If this doesn't work, steam probably saw that the files were there, but not that there was something wrong with them. In this case, you are going to go back to your library, right click on hawken, and select delete local content (Don't worry, none of your account information is stored here). After that you may reinstall hawken on steam (I think that launching the game after deleting the local content will cause a reinstall prompt to appear, not sure though).
If this doesn't work, submitting a support ticket @ https://hawken.zendesk.com/hc/en-usmay give you some more insight into the problem.