Here's another possible way that might work to prevent (or discourage) "sky-walking" on maps that are exploitable in that way ...
- Use a tool such as BSP2Map to decompile each map effected - to get coordinates for "Sky" brushes, etc.
- Fire-up Worldcraft/Hammer to get the information needed (size and coordinates of relevant "sky" brushes) from each map.
- Install Bot-Man's "Stripper2" mod on your server.
- Create a Stripper2 config file for each map, telling it to spawn "trigger_hurt" entities (with some high amount of "hurt") to effectively kill anyone that goes into the spaces associated with the "sky" in that map.
This is equivelant to a technique that I use today on my TFC server (to suppress utilization of grenades - to make it more TF2-like). In my case, I spawn a "func_nogrenades" entity over the entire map. But, it's the same type of procedure.
The down-side is:
- It's quite bit of work to accomplish the first time.
- You need to know a little bit about mapping with Worldcraft/Hammer to know what you're even looking for.
The up-side is that:
- Players don't need to download new maps or anything. It's completely transparent to them.
- Players never really get detected or flagged as a "cheat", but they do get punished (killed) for their actions.
- Once somebody does this for common CS maps, they could share the Stripper configuration files with other server admins, so they don't have to figure this out from scratch.
PS: Wow, that's a lot of stuff "in quotes" please forgive.