Routing-Filter v7.1 common tasks (templates)

Hi Guys,
i like to configure some common tasks as interpreting BGP-Communitys for LOCAL-PREF modification.
How can i jump from one CHAIN to another and RETURN to the LAST?

Or how about running common functions() with arguments? Like BIRD Routing Daemon is doing?

Also, where can i find a complete reference of available functions?
How can i set the krnt.pref_src (Kernel Preferred Source IP) per Destination-Route-Entity?

Found the solution…

if( dst==0.0.0.0/0 ) {
  set  pref-src 45.xxx.xx.185;
  accept;
}

Source: https://help.mikrotik.com/docs/pages/viewpage.action?pageId=74678285

Was a little bit confusing.
Thank you.