It si very easy thanks to our new insight api.
Simply call:
http://explorer.karmacoin.me/api/block/250422ab30233222e31bda3774f388a7972fd4f3aa59b75cf9fa3919bc740c02 , where
250422ab30233222e31bda3774f388a7972fd4f3aa59b75cf9fa3919bc740c02 is hash of latest block/or first block, depending on direction you need. It returns JSON like:
{"hash":"250422ab30233222e31bda3774f388a7972fd4f3aa59b75cf9fa3919bc740c02","confirmations":2,"size":1030,"height":300382,"version":2,"merkleroot":"740f4771da6823bf0aabb1193e5b3debbf5bbb5927238721b9e71e642fed8ecf","tx":["5ea8683cf3f216f55e93e8990f0fc6bde48bc8f00338f69f5c499dca10db1644","3e4e2533ba6985c64a056fc98d2bf7b8b1d3277662040706ae749fef85983354","dd307a531fb0b248549b2cf3ab172ba76a0672291ce6d62680a07fb2dfa8c479","722ee13ce64b9b2ce789597b181978cd6f63c0eabec74a9d527b70d0158b9a74"],"time":1409601200,"nonce":13440165,"bits":"1c0bee83","difficulty":21.45514767,"previousblockhash":"660c6c71dc5dd7b1f9ba418952d3d0a3fd716375877eed00b61d10c1804d41a2","nextblockhash":"c52cc743f0031ad1817d354d0a07aac598fef384c8464c30322f8a4c53f638e3","reward":20000,"isMainChain":true}
"previousblockhash" and "nextblockhash": are previous/next block you need to call and "tx" is array of all transaction at that block.
Than you can call for every transaction something like this
http://explorer.karmacoin.me/api/tx/5ea8683cf3f216f55e93e8990f0fc6bde48bc8f00338f69f5c499dca10db1644,
which returns info about transaction, which can be used to count movements on addresses:
{"txid":"5ea8683cf3f216f55e93e8990f0fc6bde48bc8f00338f69f5c499dca10db1644","version":1,"locktime":0,"vin":[{"coinbase":"035e9504062f503253482f0436cf0454082801d970750000000d2f6e6f64655374726174756d2f","sequence":0,"n":0}],"vout":[{"value":"20000.00000000","n":0,"scriptPubKey":{"asm":"OP_DUP OP_HASH160 d239df11538abd398c50a979eef410f6cbf12eb6 OP_EQUALVERIFY OP_CHECKSIG","reqSigs":1,"type":"pubkeyhash","addresses":["KSNiY9JzAKSuaT6wg42hCtMcfzNEoeWmw3"]}}],"blockhash":"250422ab30233222e31bda3774f388a7972fd4f3aa59b75cf9fa3919bc740c02","confirmations":11,"time":1409601200,"blocktime":1409601200,"isCoinBase":true,"valueOut":20000,"size":124}
Simply save everything into DB and than use selects and display it into fancy GUI:) Simple as that. Any developer with 6+ month experience in any language can do that.
Socoban, since you have the expertise, skills and talents.... Will you be able to add this feature into our blockchain explorer? Since you are quite familiar to the technicalities of this stuff... we beg you in the spirit of Karma