Try follow this:
1ª) Uninstall BlackShot using the program "REVO UNINSTALER" in advanced mode for removing all registery of BlackShot from your PC.
2ª) Use the program "Ccleaner" and clean your registery(important) and temporarily files.
3ª) Restart your PC
4ª) Install Blackshot again.
I assuming that your pc have all grafic cards, Direct X and drivers updated.
If not worked, then you should make a new thread in Technical Support on playone site, try explain your situation, https://forum.playone.asia/thrd/list.forum?ctgrSq=634