You are trying to combine 2d and 3d graphics in a single file. Do you want to project everything to 2D? Otherwise how should 2d and 3D graphics be combined? If you delete the shipout line and turn on the -v option you will see that your example first generates the rendered 3D output and then immediately overwrites it with the 2D output you requested. The extra shipout does 2 additional shipouts to the file My3DPicture.eps. Asymptote is generally backwards compatible but in the interest of progress...
You are trying to output 2D graphics to the same file as your 3D graphics. Since version 2.71, Asymptote separates 2D and 3D graphics. If you want both 2D and 3D output, you should shipout to separate fles like this: ~~~unitsize(10cm); currentlight=White; triple P(real t){return (0,t,0);} path3 segment=graph(P,-1,1); path segmentprojected=project(segment); draw(segment,linewidth(.2)); picture pic; unitsize(pic,10cm);; draw(pic,segmentprojected); shipout("2D"); draw(surface(tube(segment,scale(0.05)*unitcircle)),lightgray);...
dvisvgm needs the ghostscript library libgs.so or libgs.a; see https://dvisvgm.de/FAQ/
You need to upgrade ghostscript to the latest version (currently 10.03.1), see for example https://github.com/vectorgraphics/asymptote/issues/264
Asymptote: 2.91 Released
By default, orthographic projections now use center=true; the camera and target are automatically centered within the scene. The surface constructor for triangles was fixed. A bug in the WebGL flatness test was fixed. Triangle group bugs were fixed and now produce compact HTML output. Triangle groups are used for indexed surfaces drawn with the render option tessellate=true. GLSL error reporting was restored. The reported camera up vector was fixed. The map module was fixed. A syntax warning in Xasy...
I've updated the documentation to point to pages 270-274 of https://www.adobe.com/jp/print/postscript/pdfs/PLRM.pdf
Yes, looking at the installer asymptote.nsi, you are right that we do register some keys. What I meant is that we no longer modify the user's path, since that may have unintended consequences and it is better for the user to choose where they want Asymptote to appear in their path, if at all. When you check the file type association, you have the option at the bottom to search for the correct application. I did this on my system long ago and you only have to do this once. If MiKTeX is calling their...