Yes OP, I have watched the entire series of this apprentice and have also come to the same conclusion as you, that Liz is deeply in love with Chris. I would go as far as to say that Liz purposely took the fall during the tourist task to save her beloved Chris after his epic fail. I believe that Chris informed Liz about his cock up after he realised he messed up, and Liz knew the only way he would survive is if her team lost. From this point, she started sabotaging Stuart's task and carefully engineered her teams downfall, which ensured Chris' survival. In the boardroom she felt guilty and didn't challenge while Stuart was flirting with Lord Sugar. She simply accepted her fate because love was worth more than some stupid job. This is what I have observed and I believe explains the 'spark in her eye' you saw OP. Love is beautiful and full of sacrifices.