ION Group Junior FIX Connectivity Engineer interview questions

I went through four rounds of interviews: First one was the phone screening Then came the technical interview which was about 2 hours long and included all sorts of technical questions see below for details. Then also a third interview with senior management. At this point I was surprised the CTO himself wanted to interview me given it's a large company and he is somewhere in Italy... Anyway after HR scheduled the fourth interview he ignored me and simply didn't show up!! and then I got an email to reschedule. When he finally showed up a week later he seemed pissed off I didn't "get the message" that he simply doesn't want to hire me and started asking questions about technical and non technical topics not even related to the job description. It seems there is internal conflict in the company and senior management doesn't see things eye to eye with the team in question that is thousands of miles away in the UK. Anyway This process dragged on for EIGHT weeks yet HR didn't even send me a rejection email after the final interview, they just ignored me. Very unprofessional. If they called today and invited me to work with them I would turn them down. The interview is a two way process and they failed.