I looked over that file like 100 times xD I can’t believe I couldn’t find a stupid indentation error like that.
It happens . . . (a recent upload of mine had an indent error). Looking at the script you sent, you’ve already grasped all the basics, so it is just a case of getting the indentation right and you’ll be fine. It does get easier. 
There is apparently an error with *label and *goto. Check this out- this is the snippet of the code that is probably wrong.
http://pastebin.com/gR4wjTdf
If you need more code, let me know. I asked a friend to test and we got the now-infamous SCRIPT ERROR OF DOOOOM! I would use another browser to test, but I am unable to because of software stupidity.
Apart from missing a *choice at the very beginning (could just be a copy-paste error there), there is one definite error, in that lines 11 & 12 appear to be the wrong way around. A *choice must always be followed by one or more #options, so any narrative text intended for the player (line 12, in this case) must always come before the *choice line itself.
However, when corrected, this means the text beginning “The rock troll was defeated . . .” would follow immediately after the bit starting “After a hardfought battle . . .”, so if you don’t want it to actually do that, just use a *page_break on the line before *goto postfight.
Apart from those two bits (and assuming all the scene files referenced here do actually exist–tower.txt, death.txt, hold.txt) I can’t see anything else wrong with that script.
Edit: I tell a lie . . . *goto postfight looks to be indented one space too many, and *goto_scene death 2 spaces too many (this incidentally, is one of the reasons why I use tab to indent, which I set to 4 spaces–I just find it easier to spot / avoid indent problems when spaced farther apart, and it’s quicker to indent with one or two taps on tab key rather than bashing my space bar . . . but I never claimed to be conformative!).