Monte, WM has a Toe Board accessory that is used to center the log vertically on the mill deck. I have one and it works well on logs up to the 10 ft...
That must depend upon where you live or how the wood is stored. Here in NY I have never had a problem with bugs getting into my ash lumber, green or...
Ash is pretty forgiving but as you just read it will stain and/or support mold growth if given a chance. Sticker it properly so air can flow through...