newbes first map Cod4 radiant advice needed

Im a total newbee to radiant & never build a map for any game before but i belive im not doing to bad so far ,seem to be picking it up quite fast
in just a few days,so much so that ive even got my map under development,but there are some things i just cant seem to find the the right info on so thought i would ask some of the more experinced mappers for help ,hope you can!!

well here is my first map & as you can see water is a big part



i placed the main body of water in the map as a single brush & and raised it until i got the required depth above the terrain patches & cloned it as to put in water clip effects and look
is this right way to do it is it just supposed to sit like that

then i cloned the terrain patches under the lake & applied the water player clip so i will get the water noise when player runs throught it but am finding it difficullt to clip it neatly how can i do it so its just in the lake with out bits missing from the lake


are the map edges meant to stay like this



also is the skybox meant to be a full box with a floor or can it be like what ive done like a box upside down
with no floor

i ask all this because i have not been able to run the map for testing even after compiling it goes straight to the ingame cod4 menu
cant seem to worldspawn either nor build a fastfile or ad domanaion flags

The skybox is, well, just that - a full box.

If your'e trying to palce a worldspawn, don't, there's a pre-made one in every map.

not sure if your aware, but a skybox is "airtight" and looking at our last picture, one wall is missing.Make the skybox envelop the entire map so there are no leaks.

also, in regard to the water_clip layer ( the player walking bit ), you just need to lay it over the top of your existing layer - so they sit together.

hope this helps

Nice progress as for newbie... If you think u newbie - I'm 100 times more newbie :)

Well, I see u made pretty nice surface/landscape... and I'd like to learn how it was made.
Can you shortly describe how you made yr landscape? No need to make detailed tutorial, just which tools, shortcuts did u use...
Thanks in advance.

PS: SandBox2 has very cool and easy tools for landscaping, but in Radiant it is hard... :)