Yes you do need a transit visa to visit these places, if you are from nepal, you are free to roam around without a visa in the indian sub continent and i think hongkong is and singapore are also freeports but now i am not sure abt theuse places.. I dont know abt taipei but b4 in thai you could get transit visa at the airport itself but however i heard they have stopped doing that. As Six Strings said call the embassy for details.