I'm so sorry you're struggling with your quarter square triangle blocks. Those border blocks should be the same size as the blocks you used in your Ohio Star blocks. And 3 border blocks should be the same length as one Ohio Star block. I'm sorry to tell you, my blocks were a perfect fit. You've almost made it, don't give up now!!
Mine were a perfect fit too.
Your quilt is lovely! My strip and borders were PERFECT measurements, and went together like a dream. Too bad I had to have some lopped off points to make that happen! Oh well, it's a process!Good Job!