I am facing few issues in ESS/MSS.
1) For sick leave we upload an attachment, once leave request is approved, the attachment is not showing. Getting the error " You are not authorized to access archive link directory"
2) when manager is approving the maternity leave request, getting the error "work item 000000 cannot be reserved in status ERROR.
3) In the screenshot attached can i add columns TRAINER name and CLASSROOM DESCRIPTION in SAP LSO Portal.
For 2nd issue, check that leave request workflow log in t-code PTARQ or run the report RPTARQDBVIEW for that employee.
For 3rd one, you can check that columns availability by clicking on settings or personalize options in that application. If it's not available at application settings or personalize level, then you need to customize the standard powl class for this application.
There are already standard columns details but that will be invisible mode.
You need to enhance the class CL_LSO_ADMN_COURSE_POWL method IF_POWL_FEEDER~GET_FIELD_CATALOG as per your requirement to make it visible additional columns other than standard provided.