Hi DA,
I made own bluetootth board using DA14681.
Situation )
1) It is not possible to download F/W to ram ( using SmartSnippets Toobox).
2)欢迎页面上检测到连接设备的not working.
3) 'Segger Ozone' tools can access register and memory inside of da14681.
I attach captured images for this situation and schematic of my board.
Thanks,
Jeongkyun Yim
Device:

Hi jeongkyunyim,
Thanks, PM_Dialog