There were some bugs, most of which are fixed now or getting fixed soon. I will investigate the stickiness. Also, the lines were supposed to stay where they were and not reset. We are working on fixing that.
Regarding grid vs. guides. The guides have snap-to which is the accepted standard of how these things should work. Adobe Photoshop is the best-of-breed on this. A nice addition would be the ability to add a second horizontal or vertical guide to snap things in a second column. I'll see how hard that would be to implement.
The problem with the gird was that it didn't allow you to make lines independantly and had technical problems making snap-to.
Whenever we change something, even something small like this, there are some customers who prefered it the old way. We don't do it often and try not to screw you up. Unfortunately, in this case, we need to improve forward, not revert backward. Think of the features to make guides better and vote them up in the ideas section. Our product team takes these very seriously.
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