Mapped network folder... Takes a long time to access?

I have 2 machines in my office, one running XP and another running 7. I use Input Directory with these because it allows me to essentially use both computers with only 1 keyboard, mouse and basically 1 big Desktop. So it’s pretty cool, but one thing I’ve learned in using this configuration is that you need a network share (mapped folder location) to copy files between the two machines if trying to copy a file FROM the slave to the master…

Anyway, I’m curious about something… I think I have my mapped folder / network share / whatever you call it, incorrectly mapped. The mapped folder resides on the slave XP machine. Whenever I access this from the master machine (7), it takes sometimes forever to load (i.e. - you’ll see the progress background in the title bar area flood the directory path background a little at a time, indicating what I believe is it’s read progress, and once this reaches 100%, the contents of the folder are finally displayed). Why is this taking so long all the time? Is there any way to fix it?

The computers are on the same subnet sitting right next to each other with nothing to worry about in terms of firewalls, etc., so I would hate to think that this behavior is normal…

Are the two machines connected via a cross-over cable or via a router?

They’re connected through the overall network via network wall socket (they each have their own socket), so it’s probably a router.