I haven't
dealt with SVG files, but until you find an answer:
Try to open
the SVG file; rather than import
Try to
open a new document, change Resolution, and then import.
To set the document resolution:
1.
Layout >> Page Setup (or Tools >>
Options then Document >> Page
>> Size)
2.
Beside 'width', choose 'Pixels' as the unit
3.
Set the 'Resolution' you want