Any valid path combination should activate the buttons. It may not have picked up on your selection. If you pick a spline path for example-- you should see the word spline next to the button and the other buttons should activate.
"0295 is up, includes scale factor for preview image and stop after # passes. Haven't gotten to New light channel option in Lights interface yet. Check it out if you have a chance (no worries if not.)"
"Yeah-- I understand. I just think you may find you have a similar problem in this new engine with trying to estimate how many passes will be good enough. That can vary a lot.
You're always going have some error, allocating…"
"The problem is when I'm running several renders over a weekend. How will I know how much time to allocate to each one?
I wouldn't want them to run for the same amount of time, as one may over-cook to no extra benefit, while another is…"
"It's an easy feature to add, but I'm pretty sure with this new version you'll find a time constraint to be more reliable. The rendering below is probably done already, with a noise filter, or close to it."