Center for European Policy Analysis Program Officer/ Senior Program Officer interview questions

I was contacted around 3 to 4 weeks after applying. They told me it was because the high number of applications they received. I had an initial 30-minute interview with the program director followed by a writing assessment a week later. They gave me four days to complete the assessment and I think it was more complicated than it needed to be -- the first part was to pull news items (that was then incorporated into their website) and the second was a short-form analysis piece. Around two weeks later, I had a 30-minute interview with the COO and HR. They said they'd get back to me in a week, I followed up, and received a generic rejection message around a week and a half latter. I was surprised because the entire process had been going very smoothly. The people I interviewed with were very kind but I think they need more HR people. Yellow flags throughout the process: I followed up twice throughout because they didn't stick to their deadlines (I get things get busy but candidates are also looking for work) + Not sending a more personalized rejection message and not responding to my request for feedback.