How do I convert stove top pressure cooker recipes into electric pressure cooker recipes?
The biggest difference I know between stovetop and electric pressure cookers is that the electric ones take much longer to release pressure after cooking. The ones I've seen/compared take roughly twice as long (10-15 minutes for stovetop, 20-25 for electric). Biggest reason I can think of is that you can move the normal pressure cooker away from the hot stove, but you can't move the electric one away from its heating element.

As a result, I would adjust the cooking times down by 10 minutes or so to compensate.

In regards to the high/low heat, the main advantage of electric pressure cookers is that they are more energy efficient, and are designed to distribute heat well. You shouldn't need to worry about heat variance--get it up to the pressure you need and start the timer.