ok, this problem is caused by the spaceScale attribute inside the nucleus node. my scenes space scale was set to 1, now it is 0.01. I read an explanation somewhere which said spaceScale should be set to 1 while one maya unit equals 1 meter. I but have set the maya units to cm. as much as I understood this means my cloth behaved like a 150m long dress before.

with a spaceScale of 0.01 now the animation looks much better and smoother. also within those couple of seconds when the animation starts the dress is getting pulled down like actual gravity is at work.