Counter-Strike Global Offensive – How to Remove Freeze Time Forever

Yes, it is possible to restrict certain weapons with the use of certain mods.

There is a mod out there that requires SDKHooks to use, but allows weapon disabling, including warm-up rounds.

Here's the mod: http://forums.alliedmods.net/showthread.php?p=950174

TF2's version of srcds has a command-line switch -replay that will automatically exec replay.cfg for you on server startup.

This switch also does some magic with maxplayers (i.e. it adds an additional player slot and hides it from the server browser).

Alternately, you can create a cfg/autoexec.cfg and add exec replay.cfg to it, but this doesn't do the previously mentioned slot magic. autoexec.cfg is only processed on server startup and happens before the server loads the first map.