Optimation interview questions

Contacted hiring manager by phone in response to online job ad, emailed CV through and secured interview for following week. One on one interview with senior manager going through fairly standard background/experience and behavioural questions. Interview went very well, and ended with interviewer saying they will be getting me back for a second interview. Heard nothing back, so after a few days left a message on voicemail asking after next steps; this call was not returned. After a week I emailed asking after next steps and got a grumpy email back from senior manager saying that as I was the first candidate they interviewed at the start of their process they would get back to me when there was an update - effectively a "don't call us, we''ll call you". After waiting a further four weeks, I got a call from a recruitment agent wanting to put me forward for this same role. I updated the agent on my history with this role, the agent said that Optimation didn't have any candidates at that point. I called Optimation for an explanation and managed to get through to an HR person and asked them what was going on, as there had clearly been progress with this role relevant to me that I had not been contacted about. Apparently the senior manager had discussed me with a colleague, that colleague had raised my weak dot.net experience, and they had decided not to go forward with me. Totally unprofessional not to update me on this development, considering the assurances and commitments already given to me. Optimation also confused their response, thinking I had come through the recruitment agency. They showed themselves to be unprofessional, time wasting and rude.