Hello @dusza
1) Theme options store all settings of color adjustments, logo etc that has been overwritten during update and it is caused wrong setings to links and images. They can be imported from your main site. Please use import settings for theme options – import/export: http://prntscr.com/f9npsp.
2) You may use license code twice. One for main production site and second for testing and construction.
Regards,
Max Mullins