Vector cutouts

This task is driving me mad...I'm new to working with vectors and I know there will be an easy answer....please.
I created a circular maze by making thick blue concentric circles and then used the rectangular shape tool (in white) to make all the cutouts and all looks ok but this leaves me with lots of cutout shapes I don't want which gives me problems if I use the 3D tool and also exporting as an .ai file for use in 3D software. I've tried combining shapes in different ways with no success. So.....what is the best way to make a clean, sharp cutout in a circular line without using the shape tool. I tried the erase tool but its fiddly and does not cut cleanly.
I know I'm missing a (very simple) trick here???

Not seeing what you have, nor really knowing what you want to accomplish...

I would make a copy of the maze to another page so the original is untouched. On that copy, I would convert the lines to shapes, then combine shapes. And unless there were special requirements for the 3D, I would also do it in XDP or whichever Xara application you are using.

I have also attached a simple file. In this example, the drawing I began with is off the page and the lines have already been converted to shapes.

Mike

Hi Mike,
Thanks for your comments and the .xar file for me to study.
I have attached my .xar file. I think, due to my limited knowledge, I perhaps approached the task all wrong by trying to create entirely with shapes (?), even the circles are shapes with line colour but no fill colour....and now I can't combine them all into a single shape?
Ray
I don't think my xar file will attach correctly. How did you attach yours? Sorry to be a pain!
Attachment 102865

In the Pge & Layout Gallery, select all the objects that are the "cutout" rectangles. Press CTRL + 1 to make them a single shape.

Now select the rectangles that are blue. Press CTRL + 1

Select all the Ellipse shapes. Convert Line to Shape.
With those shapes still selected, press CTRL + 1

Select the single shape that was the blue rectangles. Do the same thing to Add Shapes (CTRL + 1)

Move the "cutout" rectangle object to the top above the blue shape. Select both and press CTRL + 2.

You should end up with a single shape that you can then manipulate with the 3D.

Following on from Mikes explanation and just to prove there's more than one way to do things in Xara, here's how I'd go about it, using partly Mikes Page & Layers Gallery and part the Name Gallery.

Watch in HD

Thanks guys. Brilliant. More help than I could have hoped for.
I'm a Photoshop guy finding my way with Xara/vectors so thanks for taking the time to teach me what are, in effect, basics, I guess.
Ray