how to setup this addon

Hi there

http://ayufan.eu/proxmox-ve-differential-backups/

I've been checking out this to do differential backups and looks good but I don't know how to make it do full backups on Friday while doing differential backups every Monday to Thursday. can someone please assist me

in the web interface I have it like this now

I select Friday,Monday,Tuesday,Wednesday,Thursday and select full backup every: 7. I want it to backup every Friday.

I want to be able to do the backups at 0:00