THE last applicant in the scheme plans to try her luck at Mark Six after being the final person to run through the doors of Immigration Tower a stroke before midnight. Revealing her identity only as Miss Lai, the woman, who said she was a trader, had picked up the necessary forms several months ago but decided on the spur of the moment to lodge her application. ''I am very excited to be the last person here and I hope I have the same luck in being admitted to the scheme,'' an overwhelmed Miss Lai told the waiting throng of media. ''I had not really thought that seriously about applying and then last night at home I just thought why not? I had nothing to lose.'' Miss Lai was one of about a dozen people who ran through the doors in the five minutes before the midnight deadline. Many of the people shielded their faces from the cameras and others appeared embarrassed, but Miss Lai said she was proud to be applying. Earlier, the scene was far from mayhem as stragglers of the scheme wandered into Immigration Tower. A steady rate of about 150 people per hour was maintained in the final few hours to midnight. As expected, the majority of people fell into the 30 to 40-year-old age group - those people who score the highest points under the scheme's criteria. Most applicants were couples who had met after work for dinner before going to the Immigration office. Unlike most queues in the territory, these people were mostly the financial elite, believing they had something not just to offer the territory but to offer Britain as well, should they decide to utilise their passports after 1997. Well-heeled men in suits accompanied by their power-dressing partners of the corporate world were by far the norm as they picked up what they hoped would be their lucky numbers from sleepy-eyed immigration officers. Others turned up in sports wear after an evening of tennis or jogging. ''I don't know why we left it until tonight . . . it just happened that way,'' said one aspiring Brit in tennis gear. Everyone from engineers to entrepreneurs was among the applicants and invariably people cited fears that China could change their lives for the worse after 1997. An air of determination among those near the back of the queues reflected the genuine need they felt for a back door to escape through.