If I'm understanding you properly, this is an OLD feature that's been present since when Cakewalk was a DOS program. I use it a lot.
Every MIDI track has a "Time +" parameter, which can accept both positive and negative values. You can access it by clicking on a midi track and looking at the inspector. The "Time +" setting is at the bottom of the right-hand channel. Double click it, enter a value. Negative values will make notes play ahead of time.