Hi CS,
Just to make one thing clear - OTM does not restrict you generating a report in CSV/XLS format. When you submit a scheduled report request, OTM hardcodes the DESFORMAT variable to PDF and hence the report output from OTM is always PDF. This can be modified without any issues. you have to follow the below steps to generate a scheduled report in XSL/CSV format
1. In the after parameter form trigger, modify the below line
:P_FILE := TRANSLATE(TRANSLATE(:P_DOMAIN||'_'||:P_REPORT_GID, '.','_'),' ','_')||:P_RPT_JOB||ws_date||'.'||

ESFORMAT;
as
:P_FILE := 'XXX.XLS'; ( or any name as you wish)
2. Design the report to produce an XSL/CSV output and schedule the report.
3. Once the scheduled report completes, look for the report XXX.XLS in the rptapache/htdocs folder,
4. Pickup the file and send it out using the custom script.
Please get back to me if you have further questions.
Regards,
Prabhakar