Hi Geoff,
Could You please try the following workaround to download correct APSB12-05 Updates:
1. Physically delete update file in APSB12-05 bulletin: ...\UPDATES\APSB12-05\{ec0b4f77-d2a8-43af-84e3-e69fabaa1e39}\install_flash_player_10_active_x.msi
2. Physically delete update file in APSB12-03 bulletin: ...\UPDATES\APSB12-03\{deda3103-aa1b-4e73-b16b-a3d9aa35cc26}\install_flash_player_10_active_x.msi
3. Recreate Packages for APSB12-05 and APSB12-03 bulletins. (Go to Patch Remediation Center, locate APSB12-03 & APSB12-05 bulletins, select Right Click -> Recreate Packages)
4. Check that file is updated in \UPDATES\APSB12-05\{ec0b4f77-d2a8-43af-84e3-e69fabaa1e39} directory.
5. Re-Run Installation Cycle on Clients.
Regards,
Sergei