Hi Stefan,
a content-file stored in yuuvis RAD is not processed or changed in any way - due to compliance reasons. For generating the preview the rendition-plus component unzips a local copy of compressed files and tries to generate a preview pdf of the contents. This pdf file is saved in the rendition-cache.
Therefore out-of-the-box you only have the choice of the original zip-file or the generated pdf-preview file.
If desired you could adapt the processing route in rendition-plus to not generate pdf-preview files but simply unzip compressed files and save the result as the preview-pdf. However this may only be a single file - so what if the zip contains several files? And what if it is not the expected file-type?
A better solution would probably be to implement a custom microservice that does the unzipping for you. So you could pass the viewer a URL to the custom-microservice with a reference to the content-file and when called the microservice retrieves this file, unzips it and returns the result.
Hope that helps.
Best regards
Nicolai