I love this utility! I've actually been unsuccessfully looking for something to do exactly this for a few weeks, and I stumbled on this when I wasn't looking for it.
There's one minor issue I seem to be having with it. If I restart my computer, wait for all the programs to load up (including yours, which is set to run at startup), the program is running, but doesn't have any effect on the status of the taskbar -- the taskbar simply maintains the last state it was in before I restarted the computer: autohide or not -- it doesn't change with orientation. If I exit the program and restart it, it performs as it's supposed to.
In short whenever I restart my Surface Pro (and sometimes when waking from sleep) I have to restart the program to get it to continue working properly.
Great utility by the way!
EDIT: It doesn't fail to respond every time I start and shut down, but it seems to happen whenever I restart with the Surface Pro still in portrait mode. I just tried it with it in landscape mode and it worked fine.