My midi notes are not landing anywhere that I click when my Snap On is turned on, instead landing in very random places that make no sense. Also when I change tempo of my track it has no affect on my midi or my grid. Never had this problem before.
One possible solution to the MIDI Snap problem is to goto Device Setup and check Windows Timestamp option.
On the tempo thing … depending on what you are looking at and what types of tracks are going, tempo wouldn’t change the MIDI part nor the grid. Why would it? A Part that spans 1 measure will do so regardless of the tempo.