The default for llSetTimerEvent() on OpenSim is a resolution of 0.5 sec which will create problems for some scripts developed for SecondLife where the resolution is down to 0.08 sec (once per frame).
To improve the resolution the parameter MinTimerInterval = 0.1 can be added to the [XEngine] section of the OpenSim.ini file. This will override the default set in OpenSimDefaults.ini
Setting the resolution lower than the default can add more CPU load to your server, so use the setting cautiously if you have many scripts using timers.