Great photo!!
How did you even find the sculptor galaxy?????????
I use the Nano.Tracker, as well, with a Samyang/Walimex/etc 500mm 5.6 mirror lens & Sony Nex-5N. Incl. the ballhead it's about 1.6kg.
So far got to a good 15 secs exposure with rough northern Polaris alignment - but not anything to show for, yet, because of LP, or/and moon, summer temperatures on the non-cooled Sony chip AND:
I never find anything! Bugger!!!
Re alignment once you're on holiday: you can stick a straight long stick into that tiny hole and look alongside that to align the tracker.
Also, if you have a smartphone and an astronomy app you can hold it parallel to the tracker case and sort of use it as a finder scope.
A finder scope... I so want one to attach to the 500mm lens!
The smartphone astro-app is a nice idea... but it takes me a really long time to fiddle with the ballhead knobs while aiming the cam and also keep holding the smartphone steady in place...
Btw: the nano.tracker is even cheaper in AUS than in Germany by ~80€.
http://www.extravision.com.au/nano-tracker.html