Thanx guys, this is very helpfull. Can't wait for the weekend to try this.
@ Boofredlay: Your tutorial is so clean and looks easy to do. Thank you so much.

@dsarchs said:

You could also do a quick model in Blender [or similar] using the fluid simulator and import that into sketchup. Cheating, I suppose, but that's a specific thing that other programs are just much better at [and free, in the case of blender]. Use the right tool for the job.

There's no such thing as cheating, only using the right tool for the right task. 😉

ok, thainx

Today after work I will capture step by step what I did, so you could tell me what I'm doin wrong. I'm now pretty sure that I'm making the mistake somewhere in the process, but still don't know where. 😢