Securing wood to cinder block wall

Guys and gals, I am making some changes in my gym , and installing a product called StoreWall in order to organize my gyms bars and accessories etc .
This is why I’m liking the product


Here’s are the racks on my back wall at present , which I’m removing as my options are limited . I like the mirror, as it makes the room look larger , but not at the expense of limiting my options .


Below is my photoshopped version of what I’d like to do . The yellow is the exposed perimeter of the wood that the StoreWall is attached too . I’m thinking when it’s full to expect close to 300 pounds of weight including the boards and StoreWall .

So I’m going to need to run a 2x4 horizontally across the top and bottom approx 13’ , then have vertical 2x4 on the ends and in the middle , so the French cleats on the StoreWall have a place to anchor . They have there own proprietary French cleat system .
I would like the floating effect , but worse case I could have vertical boards from the floor to the stud at the ceiling level , paint them white so you don’t notice them , and then attach boards to those . But ideally I want the floating look .

I have had limited success with Tapcon cement screws. In the past I drilled a bigger hole than neccesary ,and put a lead insert into the wall first , then drove the Tapcon into the lead insert . You couldn’t move it when it was done that way .
I was thinking about measuring the cinderblock and drilling in the hollow parts instead . This way I could use something that expands .

But now I see these , which would be used in a solid part of the cinderblock .
Is anyone familiar with them ?
I would have to counter sink them into the 2x4, as they it’s neccesary to have them flush with the board so there not in the way of the StoreWall or cleats