I bought this on a lark -- $20 wasn't too steep for a toy -- and I think it's pretty cool. However, the CC2 map you start with has to be pretty well-designed to work well in RO, and you'll end up doing a lot of back-and-forth comparision and updating to make things work out right.
I think it's best that once you're happy with your base map in 3D, start working with a copy, onto which you can drop all those "flavor" symbols that you wouldn't ordinarily use, but work well in the 3D map -- things like the tufts of grass and other bits and pieces. Those render nicely.
Also, RO's idea of a suitable color pallette might differ from yours, which makes all the difference if you want to use its texturing feature.
Lastly, make sure you build your CC2 map with the right symbols. RO only renders the "filled" symbols, not the "line" symbols -- or something like that. I tried one of my maps and nothing rendered in 3D because I had used the wrong symbol set. Likewise, if you use a lot of custom symbols, those aren't going to render at all.