Recording hand position keeps resetting previous recordings.

It sounds like when you record, all of the other recorded data gets overwritten. Is that correct? If so, the solution is to go into the Puppet Track Behaviors menu (below the camera) and turn off all but the behavior that you wish to modify, such as "Dragger" for arm and hand position.

I doubt you need to go back to rigging. Can you provide a screenshot of the timeline panel? I am not sure I 100% understand what you are saying. I think you do a first short recording, then drag the right edge out longer (so it holds the last value of the recording for the full clip). You then do a second recording - before or after the previous recording? Do you extend it out as well? What do you mean by "its all the same"? Hopefully some screenshots will make the problem clearer. I assume the second recording is overriding the first one... but that is how it is meant to work... so what is the problem exactly?