Lemon, with regard to the last one, you may want to read an earlier discussion on
P. aluta on the forums
here. Sunny has also kindly done a photographic key to show the differences.
However, as advised by many experts, we do not record photographic finds as final, particularly of the many lookalike species in the Lycaenidae and Hesperiidae, until we have voucher specimens and seek the opinions of experts like Dr Seow, TeoTP, Dr Kirton and a couple of other overseas lepidopterists before recording them.
Most of the experts have refrained from definitive IDs without having a look at the uppersides/undersides of a voucher specimen before arriving at a firm conclusion. Field shots are good for tentative IDs or to let us know of the possibility of the existence of a particular species.
There are several species pending such validation before being added to the Singapore checklist.