Hey Mark, 

Currently the only thing you can really change about the editItem border is the color. 

I did add a new delegate method that may help you though. It's called: 

in Objc: 

-(void)flowLayoutView:(IGFlowLayoutView*)flowLayoutView editViewFrameChanged:(CGRect)frame;

in C#:

public void FlowLayoutViewEditViewFrameChanged(IGFlowLayoutView flowLayout, Rectf frame);

Basically, you could set the existing border color to transparent, and then display your own view, and update its frame via this method. 

Just as a warning though, i haven't actually tested this out, it just theoretically should work.

Hope this helps, 

-SteveZ