SAGE didn't handle the escape character back-slash (\) well. If back-slash is used in script and clicking [Apply] button will generate several slashes behind. The work around is to delete any additional slash, avoid to use [Apply] button but simply click [OK] only.

Browsers cannot handle non proportional scaling for raster image like *.jpg or *.png. Engineer will normally bump into this problem when uses these images as background like factory floor or building plan, then adjust the size slightly withtout noticing it's out of proportion. When engineer start drawing SVG graphic on top of it which looks absolutely aligned and perfect, the outcome is they looks out of place slightly here and there during run-time in browser.

To solve this problem, remove the scaling of the raster image, then rescale the image to desired position by holding down Ctrl button. Another workaround is to draw additional dummy SVG object behind the raster image, and then group them together before scaling.