A web-based report would do the trick:
SELECT e.EventTime, e.Message FROM Orion.Events e JOIN Orion.Nodes n ON e.NetObjectID = n.NodeID AND e.NetObjectType = 'N' WHERE n.Caption = 'ServerABC' AND e.EventType = 40 -- 40 = unmanage node AND HOUR(ToLocal(e.EventTime)) = 4 AND MINUTE(ToLocal(e.EventTime)) <= 30
time field is not present in Event report template, you have to tweak in SQL.
what I did, if this case is with me. I simply pull the report for that particular date > export to excel > filter out events between required time.
Sometime have to go with old high school days method.....\m/....
Try this sql in a custom table resource:
NOTE: Change some_custom_property to what you need in the where clause and pick your EventTypes
select top 25
'<img src=/NetPerfMon/images/Event-' + LTRIM(STR(Events.EventType,10)) + '.gif> ' + '<a href=/Orion/View.aspx?View=NodeDetails&NetObject=N:' + LTRIM(STR(NetObjectID,10)) + '><font color=' + Icon + '>' + Message + '</font></a>' as Message
events join EventTypes on Events.EventType=EventTypes.EventType
NetObjectID in (select nodeid from nodes where some_custom_property = something) and
EventTypes.EventType in (1,2,5,8,9,14,40,41,100,940,941,942,3701)