Hi,
Never give up 
I did the process again and
When I click on Login to Google Drive a browser windows open and I can select which account to use.
Then I get a message that this app is not verified.
Click on Advanced in lower left corner. Then you have this
Continue and click on Go to Netcam Studio (unsafe) at the red arrow and you get this
Click on Allow and you are logged in as shown in the top image.
I also get an email and a text message from Google that tells me about activity on my account and if that is OK.
-Henrik