Hi Deepak, for the zoom sensitivity, do you see it only in a 3D perspective view, or does it also behave like that in one of the 2D Top/Front/Right views as well?

re: Chamfer performance, well certainly 500 holes is a lot, it's going to be normal that it's going to take some time to process a tremendously complex operation like that. How long is it taking to complete?

If your result has rotational symmetry around the cylinder, it could be possible to do only a small area and replicate the rest using Transform > Array > Circular, that can be faster.

Also another approach is to do your pattern on a flat plane which can also be easier to do with a tiled method, then apply it onto the cylinder using Transform > Deform > Flow: http://moi3d.com/3.0/docs/moi_command_reference8.htm#flow

- Michael