Are you talking about the connector pipe? Did you buy the genuine BMW part to replace it? If not, you may want to return and buy from bmw as it's been noted a few times the others do not work as well...

I would suggest cleaning up the inside bore and use some assembly lube like sil-glyde from napa to lube up the o-ring.
Put your finger in there and see how smooth the bore is, if it's rough then try some very fine sandpaper or triple ought steel-wool and ensure you wipe off any residue that's left behind by cleaning.
As for taking the the oil filter housing off, I don't think that would help near as much as having the intake out of the way which makes it way easier to get right of the mess under the intake.