Hi Matadem,

re:
> What would be the best way to adjust after flowing the rectangles on a curve?

It would probably be best to adjust the shape before you do the flow, not after it.

You could do a surface-to-surface flow to apply a bulge but also it is not too difficult to draw in a bulge.

I did that in the attached example by drawing in a curve like this:



Mirror that, then draw in lines like this:



Then use Edit > Trim to cut all that up and use this as the base shape for your Flow:



- Michael