Mod pages have an area for submitting replays. The area contains a drop-down preceded by the label "Level:", and its options are:
In addition to this, there is an input field labeled "Description:", that can optionally be used.
The assumption is that users will upload per level, not
spanning multiple levels across. The drop-down options also steer users towards this. Most likely complete level runs, but partial runs are possible, for instance to show something specific within the level. If the alternative ("alt.") or other ("other", "other alt.") options are used, the description field becomes more relevant.
oitofelix wrote:Will submitted replays be grouped by author?
Currently, replays are sorted in the order of the drop-down above. If, for example, two users each upload a replay file for "lvl 1", these files end up at the top of the overview. The rationale is that visitors are looking for replays of specific levels and are less interested in the authors. I don't expect the replay lists to ever become too large to scroll or Ctrl+f search through, but if they do I can add an option for alternative sorting, e.g. by author.
From what I've seen, players usually record playthroughs of levels if none are available on YouTube. I can imagine the same will apply to replay files. Some exceptions here and there, for instance if someone wants to share a faster run, or an alternative route, things like that. Each user can only have 1 replay for each option of the drop-down list; as it says in the upload area, additional uploads for the same option means overwriting an old replay.