its also still beta so renders should get better with each new build

after a while they peak out and it will improve background stuff and it took me 6 hours to wait for the torches to de-pixelize puu.sh/DHKH

you did see the change texture pack button?

To my still very limited experience it does work with a .zipped texture pack (john smith's)

It has nothing to do with RAM, only when you go to 3d view it might glitch out depending on the resolution of the texture pack, you might have to little ram to move freely through the 3d preview, if you narrow down the X Y size while you are moving to the position it should go way more fluent. Once in position or really near position expand the view to the size you want :)

I got my first render boiling atm, i'm not to experienced with it yet, maybe kingck has something to add, but this should get you on your way i guess. :)

Don't run it from your desktop though, that's located in the windows folder and chunky won't get the required permissions to run. Drop the folder in like D:// or something. That pretty much covers the hickups i found on my way. And do check the wiki because there are some very usefull tips on there :)