Hi Mark,
I too missed this one, though I hadn't downloaded/completed a lot of your levels after around level 50. This one was loads of fun to puzzle out, because I loooove boulders!

...and also because the level was small and there weren't too many options to confuse me. I'm proud to say that I solved this with gold by myself! I looked at your video afterwards, and I solved it the exact same way, right down to the last moves. The part that tripped me up the most was the move at @1:01 in the video. I spent last night thinking "how on Earth do I push the red boulder up?" But I wasn't thinking in terms of teamwork... the idea actually popped into my head this morning when I got out of bed, and I had to go back and finish the level!
As Kiki would say, Ace level!

(I wonder what he's up to these days...)