Increase distance between icons

Have a look at this previous post

"Adjust spacing between objects on dock"

as the space between the icons\objects depends on the icon size and not every skinner set this parameter  first I suggest to try  different themes as every skinner use different settings and in the end you will find the one fitting your needs

anyway opening the .ini file you can always tweak the dockbackground, actually if you don't find any [Tile] configuration you have to add the following lines:

[Tile]
Image = Docktile.png
ResizeIconByPercent = 95;
OffsetIconByPercentX = 50;
OffsetIconByPercentY = 50;

moreover you need to add  in the same folder of the  .ini file a transparent Image .png named (in this case) Docktile.png,

To have more space just decrease the size to 90\85\...

btw embedded in my "WhiteCristmas Docks" you can find a transparent .png ready to be copied and used 

 https://www.wincustomize.com/explore/objectdock_backgrounds/289/

let me know ! 

you can always try adding a separator 

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