Hi Arif,
I would not change the log_userid. The log_userid id sais, this user has done this action. So setting the current assignee here would just not be true. The macro gets executed by an event which gets fired after a certain time. This is a "system" event, regardless, who is the current assignee of the ticket.
Nevertheless, I understand the question to track the current assignee when this event happens.
Why not enhancing the description of the generated activity log. You may slightly change the macro code above. I would create a new macro, to make sure not to overwrite the original one. So maybe the following will work:
TABLE Spell_Macro
del fragment lock_object ob_type sym type
{ "0",
"// add an activity log. requires the macro be locked.\\0012uuid log_userid;\\0012log_userid = (uuid)\"793ED69B4E87A545BD8E911834D829FC\";\\0012// get info from event to store in log description\\0012\\0012string log;\\0012log = find_msg(63, 13, event_tmpl.sym, event_tmpl.condition.sym);\\0012log = format(\"%s\\0134nCurrent Assignee : %s\\0134n\", log, assignee.combo_name);\\0012send_wait(0, this, \"log_event\", group_leader, log_userid, log);\\0012if (msg_error()) {\\0012 logf(ERROR, format(\"macro event error '%s'\", msg[0]));\\0012}\\0012",
"0" ,"cr" ,"Add Activity Log - SLA Expired + Assignee" ,"ACT" }
Load this one time with "pdm_load -v -i -f "
It will create a new macro "Add Activity Log - SLA Expired + Assignee" and then use this macro in your event.
Hope that works (I wasn't able to test) and helps.
Kind regards
................Michael