To be on the safe side, until Alex gets a chance to upload the amended version (1a in the read-me file - and the folder has the full name, not DGS), don't swap the mirror for the ladder (you need the mirror!) ...but still take the coin above the monk's head before completing the three trials as that hasn't changed, nor has the 'extra room' left of the top snowdrift.
In the 'original' version there are also a couple of items that when swapped in the magic chest, give the right 'name', but the wrong object (check by dropping them on the ground), but these needn't be swapped. To be honest there are only a few items that need to be swapped ...but you have to include all possibilities in the game.
Other than that, there should be no other 'problems' to prevent you finishing the game.
Grandad