You can change cliff tiles and complete tilesets and add up to 16 tiles with JNGP 5.0. I recommend using it.
SAUS, I think you can change the water color in Map Options. Are you saying there is a difference between water color and tint?
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Environment - Change water tinting color to (0.00%, 100.00%, 0.00%) with 0.00% transparency
Can't this make black, red, yellow, green, blue or purple water?