Fascinating. The link to the source doesn't work. Afghanistan especially is very confusing, I can't any information on my own about these "capitals". What I did find is that Aqmola changed to Astana in 1994, not 1998.
Nice work. I'd question the description of East Timor though, as it wasn't really part of Indonesia prior to independence. It had been occupied by Indonesia since 1975 but this was never recognised; in formal legal terms it was in the same sort of grey area as the occupied Palestinian territories. The last recognised sovereign government to control the territory before independence was the Portuguese colonial regime.