M'kay, hate to bump my own thread, but although im not getting answers here I'll share the advances I made in the case that it can help anyone on my situation...
What I was doing wrong when submitting scores is just submiting the variable the way it is. Google services needs the score to be an int (at least if the leaderboard is time based, as in my racing game) so you need to use int()
Also, if you measure time in seconds as I do (just adding dt every tick to the time variable) you have to be careful when submitting the time because google expect milliseconds instead of seconds.
So, fixed from the screencap on my previous post, the submit action would be sending int(Chronometer.total*1000) instead.
In any case, when showing a leaderboard, things get unstable, at least on my game. When trying to return to the game from a leaderboard, sometimes it goes well, sometimes the game reboots, and sometimes the game just closes.
(Im using the latest cocoonJS plugin from github and since it apparently doesnt work well with recent C2 versions I donwgraded to r173)
Im still stuck at how to show a list of all the leaderboards of the game instead of a specific one....I read on ludei's site that if I just dont specify any leaderboard ID you get the list, but it doesnt work at all for me.
I read on some tutorial that the google play C2 object only works on browser and not on mobile app...is this true, or it is worth a try? (for the moment im exclusively using cocoon actions)
Any help would be appreciated!