A Visual Tutorial:
Creating an Animation in Animation Shop Using a PSP 8 Layered Image
this works the same in PSP 7, and likely in any version that has Animation Shop with it.
 
 
Step. 1
Step 2.
For the purpose of this tutorial I am going to use a simple spiral tube, since this tube already has 4 colours it will be very easy to demonstrate visually how one creates an animation using layers.
Step  3.
Once I have each of the spirals on its own layer, select  the layer you need to move.  Continue this action until you have completed the number of transitions needed to complete the animation.
Step 4. 
Save your work and open Animation Shop.
Step . 5
Open the PSP image file. and 

Step 6. click view animation.		 Step 7. If the animation works as you want it to, go to the Optimization Wizard to save it as an animation. 

If you want to create a complete rotation of the spiral this would be done by creating more layers for each image until each had come full circle, before you take it to Animation Shop 
Step. 7 Step. 7  The following frames show the Optimization Wizard Windows.
This window shows you what your animation looks like optimized This 
This window tells you the time required to download the optimizes gif at various modem speeds. The completed animation.