To change site title just go to Settings > General > Site Title. There is no problem with this in Classico theme. If you want to change the logo go to Theme Options > General > Header Settings > Logo image and just upload your logo. Also, you can upload a custom logo for some page only using page options.
We found that you left the 1star rating for our theme. All the issues that you mentioned are easy to solve and actually are not the problems. I think you just need a detailed explanation.
Would you be so kind to change the rating? Our support always helps the clients, you can check the answers on the forum and there is no need to leave the low rating to get the answer!