Virtual drive path is ignored with Material textures

Hi,
we are using Vsubst to define a virtual drive letter to Dropbox folder. This way the folder structure for linked/worksessioned/etc files stay the same for each user, regardless of their Dropbox installation directory. This solution works well on Rhino files and linked blocks, etc…

However, for some reason, the material texture file path stores the “un-virtualised” long path, and ignores the virtual drive. Because of this, the same file cannot be readily used on multiple computers, as on every Open, the user has to re-define the missing textures’ file path. Using Rh7.

Could the Texture file path be stored in it’s inputted format, instead as the expanded path?
The Blockmanager and worksession works in this way.