Normally not, however a common assumption is that mod detection is refreshed when opening the mod selection page, which isn't, so you need to relaunch 0AD.
I have found the public.zip file, and and looking through the folders for the values of the units but I can't find them.
I want to start by editing the Maiden Guards from Mauryas.
edit:
Oh, found it.
public/simulation/templates/units/maur/
The file was not color coded so I thought most of is commented out.