I doubt that Nepal is number 8. The lowest point of Nepal is 59m above sea level, the lowest point of Mongolia 560m. Nepal is #2 for highest average elevation.
Where did you get the idea that the Caspian is the largest sea in the world? Googling it will tell you that the Philippine Sea is the largest but regardless the Mediterranean and Black Sea are right next to it. If you meant largest "lake" as it doesn't border an ocean, then that should answer your question of whether Kazakhstan should be landlocked, because it only borders a lake, not a sea.
Interestingly, looking at empires in terms of % of world population, then we get several Chinese empires, the Mongolian empire, and the Roman Empire all ahead of the British Empire. In terms of sheer numbers, though, Britain is far and away the biggest.
Moldova does have a higher population than Mongolia if you include the region of Transnistria, which is an internationally unrecognized breakaway province.
For example, Wikipedia will not include Transnistria but Worldometers will.
So based on the source you will have a different ranking. It is a tricky situation.
I think many population quiz on jetpunk are taking Worldometers as a reference so we should probably keep this one the same.
The difference is not due to Transnistria - Wikipedia has 2,600,000 for Moldova and 300,000 for Transnistria, so adding these up comes to only 2,900,000 - well less than the value either source gives for Mongolia.
Also came here to say that Australia should be an answer to the camel question. Doesn't appear that any of the previous comments resulted in a fix to this error.
For example, Wikipedia will not include Transnistria but Worldometers will.
So based on the source you will have a different ranking. It is a tricky situation.
I think many population quiz on jetpunk are taking Worldometers as a reference so we should probably keep this one the same.