Chuks the senario you were given sounds similar to the British Airtours B737-200 at MAN-CFU. A lot was learnt from that incident and a fair few changes were made to equipment on board such as smoke hoods, floor lighting, and pilots would not say which exit to evacute from, extra room at o/wing exits and CODPIE was introducted.
From a cabin crews point of view we would tell you that the engine was on fire and if fire/smoke was entering the cabin we would evacuated the cabin.