Pleasde note that the menus are hard coded into PHP files, you therefore have to edit and "recode" the names.
In the meantime, doing this may create unsupported issues.
As an example, you can change the name on the bottom of the page, instead of disp^laying Chamilo 18.104.22.168, you could dispaly My site 1.0, but, you loose the capability of version auto-check.
This could happen in case of interaction between menus and actions (As I never tried, I can't be sure).
You may have to spend time to ensure there is no "bug" generated by changing the menus...
If you are prepared for this, I can spend a bit of time to see where the menus are coded
I however found a way with minimum risks, BUT, if you release the version of the platform, you'll have to do the job again!!!
Go to main/lang/<language> and you may find the menus in:
I'm not sure if some menus are note somewhere else...The best is to try with 1 menu and see what happens