Few Questions

I have a feeling that I will be working heavily with TS Tools in the next months as I have some big projects on the go. I installed TS Tools but I'm having having an issue.

I seem to get this nasty bugger message every time I start the program even those I ran those programs when I installed TS Tools. How do I fix that?
Next I just need some suggestions.

1. For the PDF reader, mine is within my Brave Browser. Should I just set the path to the browser?
2. What would be a good option for a graphic viewer?

I seem to get this nasty bugger message every time I start the program even those I ran those programs when I installed TS Tools. How do I fix that?
Next I just need some suggestions.

1. For the PDF reader, mine is within my Brave Browser. Should I just set the path to the browser?
2. What would be a good option for a graphic viewer?