Hi, what would be the best way in booking2 beta04 an dthe next versions to have my css changes that i make or the language files i change. Now everytime i do an update it overrides all my changes.

Thanks

Hello,

Joomla! API allow you to modify component views and design in templates. Template is not part of our component and you will never lose changes with any update.
Just modify only css in:
templates/{active_template}/css/{any_css_file}

And if you need modifies in views, then copy files from example:
components/com_booking/views/subject/tmpl/default.php

to:
templates/{active_template}/html/com_booking/subject/default.php

It will overwrite view in the component. Remember that html is folder for this php modifications. Next folder have to be name of the component (com_booking). Then there are folders called by name of views (subject, subjects, reservation, ...). Next are files from tmpl folder.

These files will be never updated by online update, so sometimes you will need to modify them manually for new features or repairs.