You already know what it looks like:

http://folk.uio.no/clund/nexuiz/HookRace_v1r1.pk3

The changes are mostly minor, but include:

1: Reducing the slope in front of the flags.
2: Using Hint and better Vis options to increase frame rates. I get twice the fps in some parts of this map.
3: Fixed the location info (I hope)

If you have the older version of the map on your server, please replace it with this upgrade.

Currently working on a race game mode, and porting HookRace and subseatrack to it.

All it needs additionally to a map like this is trigger_race_checkpoint entities with "cnt" set to the index of the checkpoint (0 is finish, 1 is intermediate 1, ...). At least 2 checkpoints (additionally to the finish line) are required, and they have to be huge trigger brushes (so one can't miss them when going through them fast).