Rhyming, units of measure
I thought this movie was fine, it entertained me, and it was spooky.
All over this board though people seem caught up by two things that, to them, apparently make the film laughable. The first, being that supposedly "the Ancient Aramaic translated, also rhymes in English!". But this isn't correct, there is no indication at all that the words rhyme in Aramaic at all. In fact (most likely because nobody in the cast or crew can speak Aramaic) they never say the words in Aramaic so there is no indication that the writing rhymes in the original language. Secondly, the writing was made 500-600 years ago. Aramaic was, by then, already a dead language. So whoever wrote it, Flamel himself, or someone else, was not a native Aramaic speaker and very likely did or could have spoken English. So, its not that someone wrote a rhyme in Aramaic that translated to also rhyme in English. Much more likely, given the timeframe of the writing, its that someone wrote a rhyme in English and then carved it into the stone translated into Aramaic to make it more difficult to discover even if the writing itself is discovered. So, there really isn't an issue there at all.
Second, the argument that "they assume they'd be using the same units of measurement 500 years ago that they use now." Well first, they use the metric system in France now, and second, she gets the measurement from an old alchemical chart. France did, indeed use "feet" as a unit of measure 500 years ago and that unit of measure was unchanged from basically the old Roman units the French adopted 1,000 years ago. That unit is also very similar to the "feet' uni used today in America and that used by Britain under the Imperial System. So, yeah, it does make sense.
I'm not saying the movie is perfect, but the complaints about these two issues are clearly arrived at by making assumptions that the film does not. You may assume the writing rhymes in Aramaic, but the film doesn't say it does. You may assume they're using the wrong measurement, but within the film, there is no indication they're using a modern measurement, and if they are, the unit they're using is pretty close to the same as would've been used in the time of the writing being translated.