I search for gunge, filter for upload date. 1st couple results are in date order, further down the list, it's not.

Is there an extra step I need to take? Feeling stupid

I've noticed the same problem. I think it is a combo of youtube filtering results based on other videos you've watched (for example...based on your favorites and the videos/likes of those people you've favorited) I'm sure part of it is also meant to display videos that support ad content or pay for higher search placement. (not so much in the gunge world- but it must be using the same algorithms as for other content)
Or....it could just be a broken piece of crap...

I have had the same problem for a while on You Tube. After sending your request (ie. torta na cara') just go to the filter and select 'today' or 'this week' (or 'month') which will display them in order for you for videos during that period of time. I check most evenings and can hit 'today' to get any new videos displayed the previous 24 hours.