Hamilton MPE² droplet formation

Hi there,
at the moment I’m trying to integrate a method that uses the MPE² to perform solid phase extraction. I noticed that the design of the filter plate adapter changed between different version of the MPE². I think in the current design the adapter has an open slit point to the opening of the machine and I was wondering what’s the reason for this.
To me it appears that any steps that induce even small bubbles at the filter plate noozles, every now and then droplet splash out of the MPE², which could be easily prevented if the plate adapter would have a closed design as it used to have.

Question 1: Is there any good reason for this design change, or could I build a costum adapter with a closed design to solve this problem?