Strata can do it automatically for you, using the "animation" feature. Open the Project Window, find your ship's object in the list of objects (it's helpful to group the model into a single object) and select it. Then, set your FPS to 1 and total frames to something like 36 (some multiple of 4; higher numbers are larger graphic size but smaller increments thus less jerky turning).
Next, you need to specify keyframes. If you open the properties tabs of the ship object, you will eventually come to rotation. Drag the frame specifier slider over to (totalframes /4 + 1), and set it to be rotated 90 degrees in the appropriate access. (totalframes / 2 + 1) should be 180 degrees, (3 * totalframes / 4 + 1) 270 degrees, and at totalframes + 1 set it back to 0. This last frame will not actually be rendered, but is necessary for Strata to calculate the last quarter of turning.
Now, in the Render Options dialogue box, set it to render frames 1 to (totalframes). Save as a quicktime movie or pict sequence, and you can drop the output straight onto m2s or p2s (in the Sprites collection by w00tware) to make PICT based sprites. ENrle can then be used, etc, etc.
Hope that helps...
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