I don't know if this is what you wanted, but "gate" values change when you alter a note's length/duration and "vel/value" changes with volume. For example, by default notes in 3MLE are in L4, so the default gate value is 96. If I were to make them L8, halving the default length, it would change to 48. If I were to make them L2, which is double the default length, then the gate value would change to 192. So basically, gate values for each note are based off of their own respective lengths.
For vel/value, it is based on volume. The default volume in 3MLE is 8 so the default value is 8 until you alter them to become anything between 0-15.
I've honestly never paid attention to the gate and vel/values, so I'm not sure if this is the info you wanted. Hopefully someone else can enlighten you.
Edit: Tempo can also appear in vel/value when you input a new tempo. The default t120 won't show, but any new tempos you input will.