Last.FM Support Bug & some help needed

Hi,
first of all, I've noticed a bug with the last.fm support. I began playing a song by X. Then after 10 seconds (the song is about 4 minutes long), I switched to a different song by artist Y. I listened to it entirely, and went on to the next song by artist Y.
On my last.fm account, the first song by artist X was recorded, and the last song by artist Y.
Songs should only be registered as having been played with last.fm when they're 50% over (or 100% over, if that's the best that's possible), for example.
Also, I need a little bit of help - how do I make the web player the default player?
Thanks.
first of all, I've noticed a bug with the last.fm support. I began playing a song by X. Then after 10 seconds (the song is about 4 minutes long), I switched to a different song by artist Y. I listened to it entirely, and went on to the next song by artist Y.
On my last.fm account, the first song by artist X was recorded, and the last song by artist Y.
Songs should only be registered as having been played with last.fm when they're 50% over (or 100% over, if that's the best that's possible), for example.
Also, I need a little bit of help - how do I make the web player the default player?
Thanks.