To update the included Adobe Flash Player ActiveX use Create OnePiece Adobe Flash Player True AddOn and integrate the resulting OnePiece_Adobe_Flash_Player_v%Version%_True_AddOn.cab after UpdatePack.
As an example this is v126.96.36.199 True AddOn just created with Create OnePiece Adobe Flash Player True AddOn
OnePiece Adobe Flash Player v188.8.131.52 True AddOn
Update (21 December 2016) Update (21 December 2016) Hash MD5 56982DDBF817EC17B2F868A44D84D286 Filesize: 8.92 MB (9356703 bytes)
You can also extract both the UpdatePack and the OnePiece_Adobe_Flash_Player_v%Version%_True_AddOn.cab, delete entries_Flash.ini file, copy/move newer Adobe Flash Player AddOn files inside UpdatePack, overwriting the older one and then archive UpdatePack again.