i have approx 50 clips on each of 4 sequences and if i do them one by one and render them it will take ages maybe an hour of longer. if i try and multiple select it says no clip selected. nay ideas how to do block conversion?

when you scale all imported clips to projects default setting in properties they adjust in no time at all and i will do this in future
it works out 85 percent to allow a tiny fraction for overscan.