I couldn't understand why it was necessary to bring in an external actress to play the role of Octopussy.

Couldn't Liz (or Stella) have acted the role?

Perhaps Liz, dressed as a proper Octopussy, perhaps in black leather for the kitchen scene; and then wearing that little blue off-the-shoulder thing that she wore briefly in the shop last week, for the couch scene with Chris.

Octopussy's arms could have been emphasised more on the couch scene too; perhaps Liz saying to Chris 'this is what my arms were intended for'.

If Liz didn't want to act the scene with Chris, couldn't an actor have been brought in to play the man's role?

The girls could have auditioned a row of hunks, until they found one suitable.

Alternatively, why wasn't Chris shown doing the cleaning, and asking for an extra pair of hands, while the woman put her feet up?

Hi, in the why Chris didn't do the cleaning is simple, as men seem to think cleaning is woman's work. When you look at both teams, the male candidates don't want to clean if they can help it, which for advertising purposes is a big fail.

Part of the challenge was casting for the tv advert. This was to show the candidates' ability to select the right person for the part. The right person could make the advert look better, the wrong person could make it look worse. Had they chosen someone from the team it wouldn't have been a 'creative' decision.