Hi Daniel, Welcome to the Swamp!
I wonder what you're trying to do with the (undocumented) function
(initcommandversion)... This should only be needed where you need a macro to use a new version of a command, and that's not the case here, because there exists only one version of the MLEADER command.
A usefull example for (initcommandversion) could be:
(setq ss (ssget))
(sssetfirst ss ss)
[color=blue](initcommandversion 2)[/color]
(command "_.explode")
In this case pickfirst will work, because you use the right version of the EXPLODE command.
If you modify
this code a bit, you can use it also for mleaders with blocks.