Unfortunately, a lot of converted our C6 apps a long time ago and it gets harder to remember everything involved.
Here is some good advice in another ClarionHub article.
I agree with the advice that you should fix all problems in your Clarion 6 version of the program and then remigrate over to your new version. If you find more problems, fix them first in clarion 6 and repeat.
You’ll need updated version of your 3rd party tools, especially if they contain compiled Clarion dependent DLLs.