Hello,
1. I have not began with SU25 activities for the DEV tier as of now.
2. Just to repeat, raise OSS message with SAP and let them confirm what's wrong, if any.
3. Just confirm SU24 changes made to the standard SAP tcodes in old release are in sync across your landscape (i.e. DEV, QA,PRD).
Thanks,
Sunny Doshi