Yep, exactly as you said. Purchase her and then pressing "select" does nothing. Have to choose a different female to play. Then she becomes locked for 1K purchase again, but her level goes up.
I assume this is a dead project and will never be fixed considering it has been an issue for 2+ years.
In fact. It was a project done in a short time that had some problems due to inexperience. His plans are to make a remake more similar to the project that inspired him: Redungeon