I want to add a tracker like lucky has that would grab from the prof modifier. 
So when i type "you can use this feat a number of times equal to your prof modifier" the little check boxes appear on the char sheets. 

But i cant figure out how... anyone know? 

This seems less of a bug report and more of a feature request. Something that would probably be better suited in the appropriate forum section. That could be either the General Discussion section or the Feedback section. Someone feel free to correct me if I'm wrong.

I wasn't sure where it really went tbh sorry if this isn't the place

There is no option to tie a feat specifically to your proficiency bonus in that way.

However, since proficiency bonus scales at a set pattern for all characters, it's not too difficult to implement. If you make a copy of the lucky feat you will see how it is done. Basically you set limited uses for specific levels: 2 for levels 1 to 4, 3 for levels 5 to 8, 4 for levels 9 to 12, 5 for levels 13 to 16 and 6 for levels 17 to 20.

This will result in uses being equal to your proficiency bonus.

The only time this would be different would be if something manually changed the proficiency bonus -- which is very rare and at the top of my head only the legendary item Ioun Stone of Mastery does this.

I'm currently at work so can't create a guide right now, but if I remember when I finish I can make a guide for you.

For future reference the Homebrew forum is best for stuff like this. The peeps there know their stuff and can often help with making homebrew.

Thank you so much, Im not super familiar with these forums and I hadn't noticed that one. 

So, I was wrong - apparently they added the ability to link uses by PB. Well, here's a video I just made showing how.

I hope this helps. ^_^

I have been trying to find this feature for ages now, never would have occurred to me that there are features revealed only after saving which is dumb as hell. Thanks for finding this

I'm glad it was useful!