Hi @goldstein,
Currently, the dimensions of a header logo and footer logo are the dimensions of the image you are uploading, while the banners will scale themselves to the dimensions of <The Height of the Logo> x <The Width of your Browser Window>.
The customization at the moment is rather limited, and adjusting the position of the logo is currently not possible.
There are plans to improve customizability to the UX of an FME Flow App, although it is not confirmed when these improvements could be released.
Further options to customize would be welcome, both to sizes and colours. As a temporary solution to the “logo in the middle” issue I created banner images with the logo in the corner.
@havmoejbv I’m glad to hear you have found a temporary solution. If this is a feature you’d like to see developed, please feel free to submit it as an idea. Others may be interested in a feature like this as well. https://community.safe.com/ideas