Comment 11 for bug 1672066

Hi guys, I've been reading about this problem for hours now and trying all the possible suggestions.
I also updated my inkscape version to the latest Inkscape 0.92.4 (5da689c313, 2019-01-14).
I've set the scale to 1, tried all the various units, mm, pt, px, etc. Checked DPI settings (not sure if I did this correctly, but it seems to be under Edit->Preferences->bitmap)?
I have tried installing extensions better-better dxf output and big-blue-saw-output V2.
I also copied the proposed fix in comment 3 into C:\Program Files\Inkscape\share\extentions.
I have made sure that I set objects to paths.
I have tried saving as dxfs after setting paths and objects to have no fill or stroke.

Before giving up on Inkscape I will give this one more go.

Attached, please svg with 100mm square and a 3mm hole.

When I export this and open it in my TruCut lasercutting software I get a 99.7354mm sqaure and a 2.7275 mm circle. I can scale it and combine the line to get a 100mm square, no problem. BUT the 3 mm hole only scales to 2.7347 mm.
I've set the scale in document properties to 0.99735 which gives me 100mm square when importing to TruCut, but the circle inside the square is only 2.7347mm
When drawing a 100mm square in Coraldraw, saving it as dxf and importing it to TruCut, I get the correct size.
Any help please?