You've chosen to perform a detailed upload. To do this, you'll need to supply all available and relevant information on the files you're about to upload.
In this first step, you'll be able to specify all the details. In the second step you can actually upload your files, and specify their names and types in the third step, if required.
Note: Several fields have a type-ahead function. In these you may either select an existing value, or add a new value of your own. If anything, such as OS or category is missing, please leave the field blank and add it in the Comments field.