Header photo, partial payment and mobile problems

It’s frustrating to see that you hardly explain in the forum how to solve our problems since we all seem to have the same issues. It would save you a lot of time.Anyway, here are our problems:
1. We would like to add a header photo on the pages but it shows only a small height and full width so that looks bad.
2. A partial payment plugin is integrated, according to the page of TravelWP, but it doesn’t show the plugin. Very many people complain about this and the ones who do have the plugin, complain that it doesn’t work.The theme seems not compatible with other plugins for partial payments which is not right if yours is not working and not integrated like you write.
3. After the last update the menu on mobile disappeared again. Earlier we added a CSS code that we found on this forum but now it doesn’t work anymore. We have changed the colour of the menu but it stays white.
4. The logo on mobile should be on the left side but changing it doesn’t work on mobile.
5. The sidebar refuses to be on the right side (desktop).

I think we are all in a hurry so we hope to hear from you soon.
Thanks!