going to attend Silverlake first aptitude test, can anyone tell me what the current interview process?

ps failed quintiq technical test

My technical test was conducted by 2 ppl, one senior test manager,
the total hours spent was 2 hours, the interview started with introducing of yourself, then they ask me to create schedule for the simplified version of their bus chanllege schedule . youhav to optimize it. then following they give me a code that may have inefficient or problem, you have to solve it, afterward they ask me design the schedule GUI and draw the class diagramand ask me to write using their software based on the case study. I was struggle at the first and second part