Note: your first link, allegedly to Aielund, does not actually link there.
I have seen a number of rather peculiar votes left by Mirgalen on a variety of modules, but I do not think he is a troll, just somewhat eccentric. One thing to note about him is that he apparently completely ignores voting inflation, so that, for him, a vote of 5 would be appropriate for an average module, and a 7.5 would represent an unusually good module, even though most NWN voters would never give such low votes to anything they did not really hate. If he has any serious issue with a module it will most likely get a vote below 5. If you ignore his numerical ratings completely and focus only on his comments (which, come to think of it, given the inflationary insanity, might be good advice for other voters as well) he appears relatively much more reasonable. In the case of Swordflight, for example, he criticized it for being very hard and stingy about handing out rewards, both claims that, so far as they go, are perfectly true. I consider each of those things a plus rather than a minus, but tastes in such matters differ. In the case of Siege of the Heavens, he said that playing an evil character is not an ideal RP fit for that module, which is also true, if something that should also have been obvious from the documentation before he even started playing. Nor does he downvote everything, see for example (might have to scroll down just a bit to find it) his vote on
Madness and Magic (a module I have yet to play, but one where his vote is substantially in agreement with the consensus of those who have), or on
The Sunless Citadel (so far as I know his only 10, on a module which personally I found to be thoroughly mediocre, but if others enjoy it more, great). All that said, it is certainly true that his reasons for criticizing modules (or praising them for that matter) are often weirdly idiosyncratic. Among other issues, he seems to find needing to reload very immersion-breaking and thus if a module is hard enough to require frequent (or possibly any) reloads, he tends to be excessively critical of it.