Using Inkscape 1.2.2 I have created a SVG character. In Inkscape the character has thin contours/lines. When I import the character SVG into CTA5.01 in Stage Mode, the outlines of complete character become thicker as well.
The Inkscape page/canvas settings are 2048px*2048px. I tried also different SVG output versions.
In short way: The original SVG has thinner lines/conturs then after importing in CTA5.01 Stage Mode.
Also when I open SVG-File in a Browser like Edge/Internet Explorer, the lines of the character are correctly thin. This means the SVG-File export of Inkscape shows it correct in Internet Browser.

EDIT1: I also tried Inkscape 1.0.2 version: Same issue here. I created also only on rectangle with thin lines. No matter how thick the lines are in Inkscape, the lines are always very thick after import into CTA5.
EDIT2: Provided a new comparison picture with different color of the torso line.

PS: Next day I will try to create some character without lines. Im curious how it looks like after import.

PS2: The character model I created in Screenshot is only some fast sketch for tying out the CTA5 software, before working.