USB doesn't seem to be passed through to the Sandbox at all. I've filed feedback requesting this to be a configurable feature in WSB.
Restarting the Sandbox kills it so when installing software, never accept the restart prompt.
There are WSB launcher files where you can configure vGPU and networking as well as shared directories. Unfortunately the paths to the shared directories must be absolute and cannot be relative to the WSB launcher file. I've filed feedback requesting this to be an option.