In the 1st Five Championship tournament, Blackdog and I terminated a game we stalemated. http://www.wargear.net/games/view/24621 . For the tournament records we were both awarded 0.5 wins but no loses. Is this how this is supposed to work or is this a bug?

Yes that's correct - draws are given half a point.

Draws being given 1/2 a point is all that matters for determining the tournament winner, so there is no problem with how it is currently recorded.

In principle though, I agree with Seige07. In the NHL, they have W, L, T, and Points column, where the Points column is what matters. To record just Wins/Losses, where Wins matches Points, it makes sense to have Wins + Losses add to Total Games. So, a 4-player draw would be .25 wins and .75 losses for each player. (There is 1 Win to hand out and 3 Losses in a 4-player game, and this is what evenly divides the wins/losses.) Not necessary, but it does make some bookkeeping sense. (Using W,L,T,Pts also makes sense but it is 4 columns.)

It is a de-facto 1/2 loss, since win % is calculated that way.

What about draws in an X player game with Y players remaining? 1/Y wins and (Y-1)/Y losses?

An argument could be made for your 1/y wins, (y-1)/y losses for the remaining players (with 0 wins 1 loss for the eliminated). I devilishly advocate that it be 1/x wins, (x-1)/x losses for all players including the eliminated as follows:

In Risk, a 2nd place loss is the same as a 10th place loss. Only 1st place finishes count as a full win. Rewarding the not eliminated over the eliminated is a form of placing, so it's similar to rewarding 2nd place loss over 10th place loss. Splitting the points evenly ensures that all players involved feel equal shame for the draw.