Hi xrok1, mostly I've tried to avoid having a special preview button and just dynamically do the preview whenever you change options.

So for instance for text I will just show the preview as you type automatically. (Once I get a chance to work on it some more).

For some commands it is not easy to do this though, because offering a preview means that you have to stay inside the command, and that usually means there is an extra step required to end the command by pushing "Done".

So take boolean union for example. Right now you can select 2 spheres, then push Boolean / Union, and it then calculates the boolean and finishes without you needing to push any more buttons or anything, you just move straight into the next command that you want to do.

To offer a preview would mean there would have to be a "showing preview" stage with a Done button, and you would have to push Done or right click there as an extra step before the union command would finish.

For some things it is just easiest to not have a preview and instead you just use undo if you don't like what happened...

- Michael