Hmmm, it really shouldn't be making the computer more sluggish. I'd personally found that this new version caused less problems than the old one.
As for the whys, its because we've moved into Phase 2 of the project and then want to perform as much refinement work on the computer as possible on the promising molecules identified previously before the move into the lab work.
If you wanted to try and find a cause for what you are seeing, you might like to drop in on the
forums and ask over there because I'm only an infrequent visitor here.