Im trying to develop a dynamic task expression that pulls through the selected options on a multi select lookup, but Im having difficulty with the expression code. This is the set up for the Multi Select Lookup:

And in the task expression I have tried utilizing following codes:
$new.parentEvent.W("MSL-BU")
$new.parentEvent.W("MSL-BU").name
$new.parentEvent.W("MSL-BU").shortCode
$new.parentEvent.W("MSL-BU").value
$new.parentEvent.W("MSL-BU").values
$new.parentEvent.W("MSL-BU").multiSelectValues
$new.parentEvent.W("MSL-BU").multiSelectValues.systemLookupValue
$new.parentEvent.W("MSL-BU").multiSelectValues.systemLookupValueId
$new.parentEvent.W("MSL-BU").multiSelectValuesShortCode
$new.parentEvent.W("MSL-BU").multiSelectValues.id
$new.parentEvent.W("MSL-BU").multiSelectValues.shortCode
but the result is always returned as “NO VALUE”.
I’ve tried trawling through the wiki to no success. Has anyone else managed to do this?