although it is not of immediate interest, it is still a question that has sparked into my mind and wont leave:
when making water, how would you model bullet impacs onto it? would you let it cool for a while and then tease it into the upwards-splash form with a needle? or is there something you put on after the water cools? I've a good idea for a diorama if only I knew how to do this...

experiment, i have never tried making water marks but the needle part sounds like it will work. Great idea!

Tsunami BombING

Spectre - there are two ways that I most frequently use... The first is the one you mention... wait and wait for the resin water to start curing, then if you are lucky and time things right, you can pull up and shape a splash. I USED to do it that way but no more...

The second are far better method is as follows - it is almost foolproof, forgiving of your first efforts, and looks FANTASTIC:

1) Take a small section of clear styrene rod (thin, and about 1/4 inch long" and insert it into your resing once is starts to firm up... you can lay it at an angle to indicate the direction of fire.

2) Once the resin water hardens completely, come back and coat the exposed piece of rod with a product called "Water Effects"... it is a GREAT product. it looks like white glue that is super-thick when it comes out of the bottle, but dries fairly clear. Best of all, unlike other mediums, including resin, it retains it's shape and position as you apply it with your spare paintbrush... meaning you can create the entry waves, and the irregular "splash" of the water .

3) When everything is completely dry, come back and touch up the "bullet splash" with a drybrushing of white acryllic paint.