THE United Democrats are to lose a veteran legislator in 1995. The party's central committee member, Dr Conrad Lam Kui-shing, has decided not to seek re-election. He has informed his allies of his plan to step down from the Legislative Council, though hisoptions remain open over his position on the Wong Tai Sin District Board. At 57, the medical practitioner understands that his withdrawal from the political scene could deal a severe blow to the morale of their followers in his Kowloon Central constituency. ''This is why I will follow the party's advice on whether I should try to retain my District Board seat in 1994 and keep up my presence at the district,'' he explained, adding that he had urged an early decision on whom to groom to take over his Legco duties. The party has yet to map out a war plan for the next Legco polls. But Dr Lam described Mak Hoi-wah, who is on the 12-member central committee, as his unofficial successor. Mr Mak used to work at a social welfare agency in Wong Tai Sin, before he took up his current teaching post at the City Polytechnic, also in Kowloon Central. He was seen as a key spokesman for social workers in the frontline. But his exposure dwindled when he ceased to serve as president of the Social Workers' General Union. Dr Lam has recommended that Mr Mak be given more chance to speak for the party on social welfare topics in an effort to improve the latter's profile before the next election. At one stage, Mr Mak was named as a possible candidate for the Legco by-election in New Territories West, after the death of Stephen Ng Ming-yum a year ago. The United Democrats finally opted for its vice-chairman, Mr Albert Ho Chun-yan, to carry its flag in Tuen Mun and Yuen Long. First elected to Legco in 1985, Dr Lam conceded that the United Democrats should have designated a replacement much earlier. The liberal camp is outnumbered by pro-China and conservative elements in the District Boards for Wong Tai Sin and Kowloon Central, which make up the Kowloon Central constituency in the last Legco geographical polls. The pro-China Democratic Alliance for the Betterment of Hongkong, he observed, has been diligent in cultivating the figures in Kowloon Central. ''The alliance, for example, has recently invited the chairmen of all the area committees under the district board to a dinner. Also present were senior officials from the New China News Agency,'' Dr Lam noted. Plans are also afoot for the Liberal Democratic Federation, headed by several Beijing-appointed Hongkong Affairs Advisers, to revive its district office in Kowloon City after its defeat in September 1991. The United Democrats, on the other hand, have not gained much ground in in the districts. Taking his own constituency as an illustration, Dr Lam pointed out that Kowloon Central covers a population of over 750,000 and is the second largest constituency. ''But so far, there are fewer than 50 members of the United Democrats in the area,'' he revealed, saying that even many of those enthusiastic in supporting the party's activities were reluctant to sign up. He surmised that China's tactics to discredit and isolate the United Democrats might have worked Meanwhile, Mr Mak cannot tap the popularity of the United Democrats' second incumbent in the double-seat Kowloon Central, unionist Lau Chin-shek. Most councillors have accepted the Governor's proposal to divide the territory into 20 single-seat constituency for the 1995 Legco direct elections. There has been an informal division of labour between Dr Lam and Mr Lau. Unlike his partner, Mr Lau is more conscious of maintaining his popularity territory-wide, rather than just focusing on his constituents. As a result, he has been more active in bigger issues, such as the import of foreign workers and public utilities' profits. Much of the work in nursing the constituency has been left to Dr Lam. Mr Lau, however, may not have the luxury to concentrate on major issues after Dr Lam's departure. There are already some signs of grievance even among his supporters. After the fund-raising regulations were relaxed, the United Democrats hit the streets to sell raffle tickets. The proceeds amounted to about $670,000 and the party leaders were generally satisfied with the result. However, some Kowloon Central members apparently thought otherwise. A letter of complaint was lodged with the party leadership, criticising Mr Lau for failing to assume an active role in the project. As a step towards fostering closer district links, MrLau will soon open a ward office at Fung Tak _ one of Dr Lam's power bases. In a post-election analysis, a team of Hongkong University researchers has described Kowloon Central as ''a largely working-class constituency which forms part of the industrial heartland of Hongkong''. ''However, there are pockets of middle-class and even upper middle-class housing scattered throughout the constituency,'' they added, ''To the south, considerable redevelopment has occurred in Hung Hom, Homantin and at Whampoa Gardens, where a middle-class housing estate has sprung up.'' Dr Lam has not only spotted the demographic peculiarity, but went a step further to suggest how the liberal camp should make the best out of it. Given its population, he expects that the Hung Hom district stands a fair chance of becoming a separate constituency in 1995. Dr Lam has proposed that the United Democrats should convince and back appointed legislator, Miss Christine Loh Kung-wai, to run for the seat. Unaffiliated to any party, Miss Loh is a valued ally of the United Democrats and enjoys a good reputation. How she responds to Dr Lam's proposal, however, remains to be seen.