Nope. I'm not difficult. It just stopped working.
The only thing I could suggest at this point in time is to backup '
tetra_trunk_tracker.dat' then delete it and re-run TTT and try to see if that make a difference to setting up the 'Checkbox Detection'.
If it does work you will need to send 'tetra_trunk_tracker.dat' to me so I can test it here.
Another thing to try is to run TTT as administrator and try 'Checkbox Detection'.
I don't need to do this, but it's worth a try.
I have a new Windows 10 install here (with updates) and no other stuff installed (excluding C++ runtimes), TTT is working fine with SDR#1700 and v1727.
Do you have Anti-Virus on that PC? That also may be an issue.
Latest version (v1.0.20.2) can be found here: Release post