1) I'm not sure what you mean. Do you mean you upgraded to
TenFourFox G5 38.5.0? If so, you can just delete the old copy of
TenFourFox, if any; you don't need it anymore.
2) TenFourFox doesn't use Safari for anything and doesn't modify
it or the WebKit framework (it's completely self-contained by
design so that you can use Safari simultaneously if you want to,
and many people do). You might look in the Console to see what gets
printed when you try to start Safari, which might give you a clue
to determining what actually went wrong.
I have tried to upgrade from TenFourFox 38.10.0 to 45.4.0
It downloads fine onto my G3 Mac using OS 10.4.11
When clicked on to open up it attempts to open but fails and I am just left with the high lighted icon and no tenfourfox software open in my top tool bar.
What is going wrong?