I think I found a bug in 2016-06-06 version of “Outlook - Filter Mailboxes” script.
on mailboxesToFilter()
set _result to {}
set _names to my mailboxNamesToFilter()
repeat with _name in _names
tell application "Microsoft Outlook"
considering case
set _matches to (every mail folder whose name is _name)
end considering
end tell
**end repeat
set _result to _result & _matches**
return _result
end mailboxesToFilter
should be changed this way
on mailboxesToFilter()
set _result to {}
set _names to my mailboxNamesToFilter()
repeat with _name in _names
tell application "Microsoft Outlook"
considering case
set _matches to (every mail folder whose name is _name)
end considering
end tell
**set _result to _result & _matches
end repeat**
return _result
end mailboxesToFilter