I think you left on of the $ signs in the GameConfig file, check your BSPDir setting.
** Executing...
** Command: Copy File
** Parameters: "C:\Program Files\Steam\steamapps\SourceMods\ex\mapsrc\ex_underground.bsp" "$C:\Program Files\steam\SteamApps\SourceMods\ex\maps\ex_underground.bsp"
The output of RAD looks wrong too, but the input parameters look OK to me. Ideas anyone?
Total triangle count: 1604
Writing c:\program files\steam\steamapps\shortrounduk\sourcesdk\bin\ep1\files\steam\steamapps\sourcemods\ex\mapsrc\ex_underground.bsp
0 seconds elapsed
it seems that hammer still thinks an ex_gameplay i left it the void by accident is still there becuase thats were the coordinates lead.
The pointfile wont be re-created until next time you compile, then you need to unload the old one from hammer and reload the new one.