Hollywood Park planned to conduct a full card of racing on its Cushion Track Sunday, one day after jockeys complained late in the day about "waves," or clumps of synthetic material, that a track official said were caused by problems with the equipment used to maintain the new surface.The track was closed at 7:30 a.m. (PST) Sunday morning after a horse broke down while training. Crews worked on the track the rest of the morning and the decision to race was made after an early afternoon trial run involving five horses and jockeys who tested the surface. Post time for Sunday was delayed by 40 minutes to 1:11 p.m."We had some waves in the track, which we think was from an equipment adjustment," said Martin Panza, vice president of racing for the Inglewood, Calif., track. "We hadn't had waves in the surface for 2 ½ months, but we were doing something different in our maintenance. What we were doing renovation-wise we learned doesn't work.""The track is good; it's not 100 percent but it's a lot better than yesterday. It should get better and better with each race," jockey Victor Espinoza said immediately after working a horse a half-mile. "It was hard work by those guys (maintenance crew) and they're doing a great job. As I understand it it's hard to work it at night."Panza said the problem surfaced after a front roller on the equipment used to maintain the track kept breaking and was removed by maintenance crews. The specially designed equipment has a front roller, harrows, and a back roller. "At night, when the weather cooled down, the harrows caused small humps in the track," he said. "It would drag, drag, drag material, then after awhile it would release some of the material, though it was only in a few areas."The equipment has been fixed with the front roller reinstalled, Panza said. "This whole thing is a learning process as we go, but this was a bump in the road," he said.Trainer Jeff Mullins, who keeps the bulk of his stable based at the Inglewood oval, said the problems initially began with the Friday night card when a dip in temperature and a light blanket of fog caused the surface to become uneven and undulating. The unevenness continued during training hours on Saturday and by the final races on the 10-race card that afternoon, riders became concerned about safety. Despite the continued chilly temperatures and fog in the area, Hollywood Park's maintenance crew worked throughout the night Saturday night, but by the time the track opened for training early Sunday, the undulations were so severe that it was closed so the maintenance crew could work on it. "It was like moguls on a run in Snowmass," Mullins said. "They've worked on it and it'll be alright. They're still figuring it all out; this is the first time this kind of surface has ever been used for racing -- just training over in Europe -- so I'm sure they're still working on how to take care of it. I did have a couple of horses get hurt over it early on, but we figured out not to use toe grabs (on the horses' shoes) and since then everything's been fine." Cliff Sise Jr. agreed with Mullins: "All my horses would be over here if I had the stalls. I think they might be working the track too much, I'm not sure. But I'm sure that once they get the bugs worked out it will be the best track in the country."Panza stands by Hollywood Park management's decision to become the first California racetrack to install a synthetic surface, which the California Horse Racing Board has mandated for all tracks by 2008. Cushion Track, manufactured by Equestrian Surfaces of Burnley, England, was installed in early September, well in advance of the fall meeting that began Nov. 1."So far the number of injuries is way down," Panza said. "The first seven to eight weeks of training it was staggering how few injuries we had. Then as we got horses with physical issues from other tracks, the numbers picked up, but they are nowhere comparable to last year or previous years. This time last year I had 1,100 horses stabled here; this year there are 1,800."One thing people have to realize is that this track or any synthetic surface isn't a miracle worker. Some owners and trainers have shipped horses here because they have problems and they think the track will help. It's good, but it's not going to solve a knee or ankle problem."Correspondents Margaret Ransom and Tracy Gantz contributed to this report.