I have used logmein to remote connect to the show computer, but I find it slow and awkward and I use remote desktop with customers all the time.
Cable length of USB cables is not an issue when you are carrying a laptop / netbook plus a dongle / tx unit around the layout doing troubleshooting. I could mount and have in the past both the dongle and the TX onto a small board, but I would still be limited to having to have a power connection for the tx. If walkie talkies can run off small batteries then so should this transmitter. Remember this is not for show purposes but for layout troubleshooting. I suppose the current tx could be jury rigged to run off a battery with a cable to plug in in place of the wired transformer, but I am not electrically knowledgeable enough to know if this could be done.