1) In a FLIC, if you have the same picture twice (or more), only an index is added to the frame to tell the flic player that it has to show the picture again. You can for example take a single GIF and output it trough Video Post hundred times. The resulting flic will have the size of the single GIF plus some bytes to tell the flic to repeat the first frame many times. Because the technique of putting each frame twice is not so easy (unless you have Animator Pro), and there is no positive effect to be expected, I would suggest to read on:
2) In your case it would be the same to tell the flic player to insert some delays between the frames to give the player enough time to load the next frame. Every flic player has commands for this purpose. The default flic speed is 5, the maximal is 0 (no delays), and you can set any number (the bigger the number the slower the flic). Consult the documentation of your flic player for more. The drawback is that the flic doesn't play smoothly anymore.
3) The tearing appears when the difference between two frames is too big - a great portion of the screen has to be updated. The best decision (but a hard one!) is to double the lenght of the animation. This would insert an additional intermediate frame between each two frames (and not repeat a frame). The movie would play much smoother and at the same speed like in 2). The flic size will not be doubled (although increased), since the differences (Deltas) of the frames will be smaller than in the first case. The RENDERING TIME will be doubled, which is the main problem. If you can afford longer rendering times, try this one!
To double the lenght of the animation, go to Time/Scale Time and enter the doubled size. All keys will be scaled proportionally.