Based on the information provided, I believe there are a few factors contributing to the situation where the device enters DAPLINK boot mode unexpectedly.

Firstly, it's possible that an abnormality occurred during the program download process due to an outdated firmware version. This anomaly might have triggered the DAPLINK's button reset functionality, leading to the boot mode activation.

Regarding the issue of the DAPLINK.bin program not taking effect when dragged from GitHub, I would like to highlight three potential reasons:

1. Pin Definition Mismatch: There could be a discrepancy between the DAPLINK pin definitions on the development board and the program's pin definitions specified on GitHub.
2. Special File Format (RBL): To enhance program security, the official firmware utilizes a unique file format called RBL. The RBL file contains a header that allows for data verification. Consequently, directly dragging the .bin file into the DAPLINK may not yield the desired outcome.
3. Bootloader Functionality: It's worth noting that the onboard DAPLINK on the development board incorporates a bootloader feature. Therefore, the DAPLINK's link address should not start from 0x08000000.

Considering the complexity of the situation, I recommend seeking assistance from the RT-Thread official team. Their expertise and guidance will be invaluable in resolving the challenges you are facing and ensuring the successful implementation of the desired functionalities.