I have made a polar grid and I want to fill in some of the circular and angular sections of the grid with different colors. I'm trying to make a basket weave design within the polar grid with different colors using the paint brush tool I think. I'm not sure how to select one of the grids so that the paint brush tool will fill only that grid. Help would be much appreciated. Thanks!

As the polar grid extension produces a group consisting of circles and straight lines, and filling the boxes in between them with the bucket tool is not very exact, I would suggest the following procedure:

- select the 'grid' you rendered with the Polar Grid extension
- Ctrl+U to ungroup
- Ctrl+K to combine (remove fill to see that all lines are still there - you may also need to set a stroke width to see the strokes)
- Duplicate the result with Ctrl+D
- add a fill color to the duplicate
- union the duplicate with Ctrl++
- put the duplicate below with PgDn key
- now select both objects (duplicate and the combined grid), do Path > Division to cut the lower object into lots of pieces.
- select the pieces, color them as you like using the palette or the Fill + Stroke dialog.

Thank you Moini for your help. I tried the procedure you suggested and the end result was a colored round circle in the shape of my original polar grid with no grid lines. Not sure what I'm doing wrong.

If you want grid lines, you might need to add a stroke (see step 3).
If you want the grid lines to be non-uniform, i.e. different widths, keep a copy of the render result on top.

Try again slowly It should be working.