A closer look an comparison reaveals that Inkscape has this tag that chrashed carbide.ui:

style="-inkscape-font-specification:Verdana;font-family:Verdana;font-weight:normal;font-style:normal;font-stretch:normal;font-variant:normal;font-size:42.31547896px;text-anchor:start;text-align:start;writing-mode:lr;line-height:125%"

It seems like it is the "-inkscape-font-specification:Verdana" part that carbide.ui won't "eat" :-)
If I delete that carbide.ui will import the file.

But that is a bit extra work...

So if anyone know how to make Inkscape NOT write that illegal tag...
Or someone could fix carbide.ui so that it will read thar tag...

Then :-)