PLANT yourself in front of a satellite TV screen tonight to see live coverage of the Hongkong rugby team's first match at the World Cup Sevens from Murrayfield in Scotland. The team, who disappointed at this year's HK Invitation Sevens when they were knocked out of the lowly plate competition, face a tough opening match today against England (World Cup Sevens, Prime Sports, 9pm). HK Sevens champions Western Samoa have alsobeen drawn in the same pool as Hongkong, so the lads, skippered by Craig Pain, are going to need all the support they can get. Australia's opening match against Taiwan will also be shown live. TV coverage of the Salem Open tennis championship (Pearl, 9.45pm) begins with Andrew Sams and Don Bozarth introducing highlights from matches played so far at Victoria Park. Tomorrow and on Sunday they'll present live coverage of the semi-finals and finals. COP thriller Blue Steel (World, 9.30pm, Original Running Time 102 mins) may be short on plausibility but it's long on talent, with Jamie Lee Curtis (daughter of Janet Leigh and Tony Curtis) giving her best performance yet as obsessive rookie cop Megan Turner. Megan gives her career a real kick start when she manages to shoot dead an apparently unarmed robber on her first day out. Then corpses start turning up all over the place, killed with bullets fired from her gun and even marked with her name. Broker Eugene Hunt (Ron Silver) is somehow mixed up in this, but who's stalking whom? You'll guess, of course - the script really is ludicrous at times - but, love it or loathe it, this manic thriller has some stylish moments. GREAT to see the ancient advert for Kheu Hua Chen Chiew - the Chinese liqueur that is apparently popular for weddings, parties and all special occasions - is back on our screens yet again. It's the one in which a young Chinese couple turn up at a party where a lot of people are ''grooving'' enthusiastically to no music whatsoever. The ad's been around so long that, with the current craze for flares, platforms and psychedelic colours, its party-goers now appear bang up to date again . . . apart from the dancing anyway. SOMETHING very strange has happened to the 7.30pm programme slot on World and Pearl. Barring a couple of exceptions. It suddenly contains programmes that won't have viewers putting bricks through the TV screen. Some - witness The Simpsons, City, Eye on Hongkong and Murphy Brown - could even be described as entertaining. World's newest series The Powers That Be, a sitcom starring ex-Dynasty star John Forsythe as a senator, is the latest to fall into this category. It's patchy certainly, but viewers should find themselves perilously close to raising a chortle.