How to import inductor created in sonnet in to Cadence without DRC errors?

I need to create 5nH inductor in UMC 0.18um technology for high frequency(10GHz).I am using sonnet for that.I created inductor in sonnet by defining cell size of 0.01um since standard grid size of 0.18um technology is 0.01um. But after exporting it into Cadence it give me DRC errors.(Off-grid errors).Could anyone suggest me a method to remove this off grid errors.Is there any way to define the grid size in sonnet.

This occurs generally octagon shaped inductors.Diagonal patterns of the inductor can be off-grid.
In order to correct this problem,diagonal lines/shapes should be slightly shifted or should be made on-grid manually.
Or, you have to align X-Y grids in Sonnet as 0.01um.

Thanks for the information.But,I set X and Y box cell sizes to 0.01um ans snap grid size to 0.01um as attached images.But still it giving this DRC error.How we align X-Y grid in sonnet as 0.01um is there any tools to do it?.Once I defined cell sizes to 0.01um I can't see any grid line to do it manually even with zooming.

Thanks to Dr.Volker,I solve the off grid error.The method is as follows after setting the cell sizes to 0.01um.

"From the user interface, you can set a cell size and force all points to snap to the cell size.
Edit > Select all
Modify > Snap to > x,y
but there might still be some precision problems in the file afterwards.

The reason:
Internally, Sonnet is using floating numbers to represent the coordinates, so some rounding issues might happen.
Sonnet made some changes in that area, so that you should see less problems with the latest version (13.56/14.x)

To see if your Sonnet project has rounding problems, you can open the *.son project file in a text editor
and check the polygon coordinates for something like .9999 that indicates precision problems."

But Still I am getting skew edge errors in the DRC run.Does anyone know how to solve it?