there are 2 file upload 'slots', one is FILE the other is IMAGE. In the form.html file, which formats the upload page, there are 2 tokens for each one, [FILE] and [URL] for the file slot, and [IMAGE] and [IMAGEURL] for the image slot. the URL versions allow you to enter a URL while the other ones allow you to browse and upload a file into that slot.
In the current YouTube template, form.html has a [URL] token, so when the user enters the URL to the video it is stored in the file slot. In the template which displays each item, there is the object tag which displays the player and it uses the [FILEURL] token to display the contents of the file slot without any special formatting or spans around the value, just the raw data value which is the URL.
So, if you want both a file upload and the video URL, you need to make some changes to those 2 template files.
1. modify the form.html file to use the image slot instead. so, change the [URL] token to [IMAGEURL] so that the URL entered by the user will be stored in the image slot instead, then change the template.html file to use the [IMAGEURL] in the object tag instead of the [FILEURL] so that the player will look in the image slot for the video URL.
2. now, you are using the image slot for the video, so you can now add a new [FILE] token to the form.html file to allow the user to also upload a file, and add a [DOWNLOAD] token on the template.html file to render a download link to enable users to download the file.
that should do it. if you have any questions or problems, let me know.