I tried making a crystal points code but it appears to change every time you enter town. Then once I found it, the game would freeze when you left town and returned to save. Finally got it to stick by finding the address, modifying, then turning it off, buying a skill and leaving town.
Couldn't find gil code but I found the address for materials/drops etc, just changed to 255 and sold over and over. This one is easy to find doing a search selling items, just keep doing decrement on the research and you'll find the address after 3 tries. Adding a value gives you the item, so if you start adding values to the surrounding addresses you'll start unlocking random game items.
The table for offsets start at 0x40 being 8 bytes per entry with 48 entries.
Entry:
4 bytes - offset
2 bytes - size of entry
2 bytes - number of entries
Entries:
0x1c0, 0x388, 0x01 - Character Information
0x548, 0x1c, 0x12c - Weapons
0x3108, 0x1c, 0x64 - Torso
0x2618, 0x1c, 0x64 - Head
0x3bf8, 0x1c, 0x64 - Leg
0x46e8, 0x1c, 0x64 - Shield
0x51d8, 0x20, 0x64 - Accessories
0x5e58, 0x58, 0x64 - Monsters
0x23140, 0x01, 0x40 - Consumables
0x2ff98, 0x01, 0x190 - Materials
0x30128, 0x01, 0x64 - Atmaliths and Magicite
Weapons, armor, accessories, and monsters require an ID and the location within a table. Without those two, the game will crash.