object isn't following curve

hey im trying to make part of a city on blender and i’m trying to do the streets first by making paths and telling a square to follow the path with an array controling the size using the curve length but thw square is following the curve just not in the right position i got it to work once duplicated it reset the origin to where i wanted it to start applied rot, loc and scale but the duplicated meshes are not working like the originals. its not the first time this has happened but i want to understand why its happening instead of manually moving it into place. I’m adding the .blend file if you want to see whats going on


citymap.blend (414 KB)

you have to understand 3D.
Thats not easy,
if you search the forum
you will find a lot of postings
about to solve such situations
with confusing settings.

You have, not only in blender,
in every 3d-software:

location in the from of x,y,z-values
these are not all the same and every
location-data depends on the context it is used.

And this makes it easy to do thing wrong and
look like nothing is working any more, because
the changes tweak the wrong parts.

There is global location,
local location,
differential locations (transform),
and the combinations of
these with other objects and their locations
used in parenting, constraints, modifiers.

And all these are evaluated in different order,
some orders can be tweaked and if set at
different eval-place, the result will be very different.

From your description of your changes it is very likely
you mixed those modes and wonder why you get totally
different animations for those different settings.

ok the locations i already know about but i dont know how it works with the modifiers in this case the curve modifier if i add a new plane where the curve starts for example with out changing anything and add a curve mod and link it to a curve the plane becomes a line why? i think its a problem with the curves when i make them in blender it seems to work fine (i imported them from coreldraw)