Here is what the patch does:
-Applies gbata's RTC patch
-Adds a clock to every Pokemon Center
-You can reset the clock at any Pokemon Center
-You can view the time at any Pokemon Center
-The location of some clocks were moved for the sake of consistency across all versions and for aesthetic purposes.
-A script event was added to the clock in the Pokemon Center of the Battle Frontier.
-Clocks are now color-coded for each version; green for Emerald, red for Ruby, and blue for Sapphire.

These patches were tested on the VBA-M emulator and GBA hardware with an EZ-Flash IV.

All editing was done in Advance Map and consisted of creating a new palette and editing/moving/creating tiles.

Also, for anyone that cares, Emerald gets upset when you edit its existing tiles. The tileset had to be enlarged by 8 and new tiles created to avoid graphical glitches. This fixes the problem of missing and/or corrupt tiles appearing in-game.

File: 1961 - Pokemon - Emerald Version (USA, Europe).gba
  Size: 16777216
  CRC32: 1F1C08FB
  MD5: 605B89B67018ABCEA91E693A4DD25BE3  
  SHA-1: F3AE088181BF583E55DAF962A92BB46F4F1D07B7