IT is still touch and go whether Michael Jackson's concerts will go ahead at Sha Tin racecourse next month as originally planned. Fax machines at the offices of local promoters, led by Arena's Allan Zeman, and Jackson's management team in Los Angeles worked overtime yesterday with proposals and counter proposals for the Dangerous world tour to be able to kick off in Hongkong. But by late last night little headway had been made, the lack of a viable location being the major headache. With Jackson still insisting on putting the start of the tour back by nine days to August 24, threatened disruption to preparation of the racecourse for the opening of the season on September 12 rules that venue out. However, the Royal Hongkong Jockey Club agreed that the concerts could still be held on the proposed new dates if the 90-metre long and 30-metre high stage was erected on the forecourt instead of the training track. A member of Jackson's technical team flew in on Monday and after inspecting the venue, he advised Los Angeles the stage could be built in the new area if one of the two giant video screens that flank the stage is scapped and the bank of speakers on the wings is reduced from 12 metres to six. This, apparently, was considered unfeasible by production manager Benny Collins as the twin video screens form an essential part of Jackson's act and the banks of speakers serve as a screen for the quick changes of clothes that are required of the dancers on some numbers. Yesterday Zeman faxed a personal letter to Jackson pleading with him to re-consider changing the dates, explaining that 70 per cent of tickets for August 15 and 16 had already been sold and emphasising the problems for a venue on the new dates. Zeman also wrote to the Jockey Club asking if they would consider allowing the concerts at the unfinished Hongkong Stadium in late November. Jackson's promoter Marcel Avram has offered this as an alternative as there is a gap in the world tour schedule after the Asian leg ends in Jakarta. ''In my letter to Jackson I asked if it might not be possible to work something out . . . and fulfil the Hongkong dates as planned. I told him we are praying for a miracle,'' said Zeman. American Express, whose cardholders snapped up 14,000 seats in a preferential booking offer, advised last night that no accounts would be billed until the concerts were set and ticketholders confirmed their purchases for those dates.