in "sc-actions-kwave_zoom_original.svgz" file there are a couple of text-align
tags it looks like imagemagick ( convert ) doesnt like it and couldnt convert
it to png and it fails to generate "kwave_zoom_original.png" file with error :

convert-im6.q16: non-conforming drawing primitive definition text-align'
@ error/draw.c/RenderMVGContent/4300.`

I have removed those 3 tags and regzipped svg looks like working correct