SolveSpace: snap to line ends?

I found this site researching a CNC build and saw SolveSpace. I like how simple it is, so thought I'd give it a go with a current sheetmetal project I've got going on.

It's got two holes in the middle, so I opened up Rhino to dim out the drawing so I could sketch it out in SolveSpace. After the two holes and construction lines to the diagonal corners, the square for the body is off by 0.2mm. My only guess is that new lines or circles do not snap to existing lines?

I should go watch the tutorial vid...

Thanks,
Chris