When you copy/paste pay attention to the time clock. You want to make sure the click count on your Paste action matches the on from your Copy.

Example: If you copy from 2-1-12 Thru whatever, make sure you Paste it at X-1-12 so everything lines up.

If you are going to use the Repetitions option (paste the same thing multiple times in a row) make sure you get a whole measure section so it pastes correctly on the 2nd 3rd 4th iteration.

Example
Copy 2-1-0 thru 12-4-119 (if resolution is 120) so that when it pastes multiple times it all lines up.
By this I mean the next iteration starts where the first one ends. So if you copy X amount of bars and three beats of data, the 2nd iteration will be a beat early, the 3rd will be 2 beats early .. etc Copy full measure increments to make it work right.
Some people use the Bars window for this since it selects full bars, however it is also OK to copy from beat 2 of a measure as long as you end the copy at the tick that makes a full measure.
Example
You can copy 2-2-14 thru 12-2-13 (which should then be pasted at X-2-14)...

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