You can push the assembly down with your foot, like you did on the rear, but it will not drop to the ground, making it more difficult. Normally, once those 3 nuts are removed, the whole shebang falls to the floor. Not so on the e90.
So, grab those spring compressors (mine had 19mm bolts on them), and put them on opposite sides of the strut spring, with the bolt head on top. I could grab 3 coils on each side. Make sure when tightening, you tighten no more than 5 turns before doing the same to the other spring compressor. Eventually, you will have them as compressed as they will get.