Hello,
I have the same "problem " to solve with pavers along a curved path.
first of all, your work looks neat and tidy and i assume that you work with high precision/detail.
here's my solution:
The main issue with curves in SU is that they are not adaptive like in e.g. Auto Cad.
In SU curves are line segments aligned to appear like a curves.
Okay, knowing this fact, lead me to the conclusion, that by using paver units for soldier borders you want to draw your curves accordingly.
e.g. your paver is say 6 inches wide by 12 inches long so now you draw a curve as desired, the next step is to divide the calculated length (window---entity info) by the paver width (in this example 6 inches plus spacing) and apply this result to your arch (segments).
now your arch/curve will precisely match your pavers. for your inside arches you may have to do some angular calculations to determine the spacing or you could just offset another arch in this example it would be 12 inches and do the spacing as before.
so now that you have the layout geometry you can use the "path copy" and your result should be okay.
Now you definitely want to turn your rectangle (paver) into a CoMPONENT! Why?
here is an example: lets say you used the path copy tool to distribute your paver's along the path, it seems though they followed the path but are not correctly aligned.
Easy fix here since they are components, insert a single paver into your drawing, make sure it is aligned to the red blue axis.
double click the paver to get into the component (edit component mode)now zoom to see both, the path and the paver component you're working on.
Now select all geometry in the component and move or rotate from edge to edge until you see the correct alignment of your paver along the path. All the other paver's will align accordingly, that is the power of components!
hope I was of some help here.
I don't know how to attach a file to this post so I can't send an actual example file