I'm not sure what you mean by "recording" the waves. You can use animation controls to animate the noise function that is the basis of the water shape. This is essentially what JimB did in his recent wave motion animation tests. You can start by using a Transform shader to Translate the position of the water's noise function over time. Translate in the X and/or Z direction for horizontal movement, and translate a little bit (much less than the other two) in the Y direction (vertically), which will give you some variation in the shape over time (rather than just simple horizontal movement with a static shape).
As for saving your workspace, that's not currently possible but we do hope to add that in the future.
- Oshyan