If it goes too fast, you need to go to the preferences and constrain the frame rate (it's a checkbox on the bottom). If it's too slow, I think your out of luck. Other than hiding everything, there is no cure in Anim8or that I know of. This is most likly a simple lack in processor power or your graphics card is slow. If your running a laptop, make sure you are not on energy save mode, it turns down the microprocessor to save energy, (by default, it is usually on when you are unplugged). To fix this, go into your powersave settings, and if you can, create a custom setup from the high power settings. Then you can do things like turn down the brightness of your screen and such, and set your computer to run your custom settings when unplugged. That's the best I can think of. If this doesn't help, you'll have to think through the timeline and imagine what it will look like. Hope this helps.
