Hi Dan thanks for posting to Lucid Community! I'm not quite sure what you mean by resizing all the components but when you import a custom shape from a SVG file the shape should be resizing accordingly. If you switch between different platforms by exporting and then importing as an SVG file the formatting may adjust to match the unique product configurations. Unfortunately that may mean that it doesn't appear exactly as expected. 

If your SVG is importing correctly but doesn't look like the original after resizing I would highly recommend building your custom shapes within Lucidchart which will allow you the continued ability to customize individual shapes as well as building custom shape libraries for reuse. Please check out our Modify Format and Style Shapes article for more information of how to create and customize shapes in Lucidchart.  Feel free to comment under the thread if you have any further questions! Hope this helps.