My comments are given after the quotes:
1) "因此中國的對外用詞往往被生硬地扣上蘇聯意識形態，這是西方所慣用的政治伎倆。劉曉明...非常可笑，是...恥辱"
If "西方所慣用的政治伎倆" is true, 劉曉明's answer is smart since a simple "yes" or "no" will make him fall into the trap.
2) "劉曉明一個中國駐英大使，連自己是不是“共產主義者”都說不清楚，非常可笑，是中國外交係統的恥辱".
There is nothing wrong with "說不清楚" since the definition of 共產主義者 has changed with time. It is difficult to "說清楚". If 共產主義 means 專製 accoring to someone's definition, Liu's answer is perfectly fine. There is nothing to be shamed about.
3) "丟人的是劉曉明這種缺乏政治自信".
What part of Liu's answer shows that he is lack of confidence? Did he have to say "China is a communist country" to show confidency even he does not think so?
4) "政治底氣是一代不如一代 ... 連自己都不敢公開承認自己是個共產黨國家" vs "中國早就不是“共產黨國家”了".
It seems to me, according to someone's logic, Liu would look bad no matter whether he answered yes or no. It does not make any sense.
5) "如果沒有上級許可，他劉曉明哪敢發出如此石破天驚的言論"
Can China change or not? Why cannot we consider another probability that Liu is confident enough to do the interview without knowing the questions in advance, and he actually expressed his personal opinion?
6) "這個認識轉變雖然讓共產黨多少會“有失顏麵”" and "改正這些錯誤，這並不丟人。"
According to someone's logic, "有失顏麵" is "並不丟人". It does not make any sense.
