Hi,

You can implement any kind of snapping be overriding node's *Modify and *Create methods as in http://mindfusion.eu/Forum/YaBB.pl?num=1350308635.

However, I think you will get most out of the control's built-in features by modeling the pipes using DiagramLinks. E.g. you could automatically create intermediate "joint" nodes between links as shown in the SiteMap sample project: if a link is drawn unconnected, there is a new node added automatically and set as its destination; if a link is drawn to an existing node (joint), that node remains link's destination. Then moving a joint node would also automatically update its related links / pipes, which you would have to implement yourself if using only nodes.

I don't know what your requirements are, but using links might have additional benefits, such as modeling pipe flow direction, and built-in path finding.

Regarding isometric grid, our developer thinks it will be easiest to apply a skew transform on the standard grid's Visual, and overriding the Diagram.AlignPointToGrid method, which is used internally when aligning items to the grid. We'll try to make the respective members public / virtual in the next few days to let you do that.

I hope that helps,
Stoyan