Tom,
My first bin I cut a 1 by 12 into pieces and screwed it into a box. It worked and still is holding worms but when I culled out my worms I needed a new container. I used a regular rubbermaid bin. Its about 2ft by 3ft I did not even drill holes in the bottom and the worms love this bin the best. I leave the top off since these worms are 2 and 3rd generation so they dont climb out. The other questions you had is about the cracks, I think they will come out but you never know, also the light goes on at night to keep them away from the top of the bin so they dont crawl out. The rubbermaid bin is perfect try to keep the moisture right, not to wet and not dry.
