Isn't it annoying when so much room is used in a video? Who has that much space to work out at home??
Well, enough griping: for the double grapevine, I've done a "baby step" grape vine, as has already been suggested. You could also do a grapevine and add on a 4-count move of your choice, or invention!: for example: grapevine to the right, step forward left foot right knee up, step back right foot left knee up. Or a grapevine with two jacks.
For the eight steps forward, I concentrate on the vertical and do four steps at 1/2 the pace of the 8 steps, bringing my opposite knee high on each step.