1) Yes. But nothing too important.
>Some of the pillars that comprise the corridors of the four floors of the abyssal ruins are colored purple and marked with mysterious letters. These letters can be transliterated into letters of the roman alphabet using the correct cipher.
http://bulbapedia.bulbagarden.net/wiki/Abyssal_Ruins#Mysterious_letters
2) Here:
> There are four levels in total. To get to the second level, you must travel directly to the central area upon entrance, without deviating or back-tracking. Press A on the pink block with writing on and it will move.
>On the second level, you need to use Flash on the pink block indicated on the map below, to get to the next level. On the third level you must use Strength on the specified block to get to the final room on the fourth level.
http://pokemondb.net/maps/abyssal-ruins
3) 500.