benny, you can patch digitally with your laptop and the ua-1d, though you won't be getting a bit-perfect signal. as for battery life, coming from someone with experience running a full-sized vaio, you're not going to make it through the whole show. if your laptop uses the same sized batteries as mine (BP1N or BP71A) you can borrow my spares...my laptop has the ability to remove the floppy and use that bay for a second battery.
additionally...there are a few settings you'll want to change (power management being the first and foremost) so you don't run into problems while recording or shutting the lid causing your system to power off.
if you want to borrow my 7-pin, you're welcome to it. in fact, you can use the core-sound 7-pin i have pretty much indefinitely, until i need to sell it to buy crack. also, you can use my m1 tonight if you want. i'd really like to see that show but cannot afford a ticket right now.