Ok, since nobody else replied, here's my take:
The clock stops for the day at midnight GMT+2. After that whatever you earned is transfered to you the next day.
So ofcourse whenever you get a payment your balance goes back to zero, either you are doing it solo or via onlinedragon.
But here's the thing. I've also noticed my earned amount going down. I was up something like 312mrai today and went to surf the web and do some stuff and when I got back it was at 300. Found it strange and thought I was going crazy. So I solved a few more captchas and it instantly saw it going down again like 0.8mrai immediately after solving a captcha.
I'm pretty sure this is not normal..
Ok so the devs say this is normal and pointed me out to this:
personal reward = personal claims / total claims * max quantity distributed
I don't think this explains it and I'm waiting for more info.
EDIT:
Personal reward is just estimation for a moment.
1 hour: you made 100 claim. Others made 9900 claim = 10,000 total. You will see 100 * (400,000 / 10000) = 4,000 Mrai reward
So, you are happy & stop.
24 hour: you still have 100 claim. But total claim is 200,000 already! You final share is only 100 of 200,000 claims. 100 * (400,000 / 200,000) = 200 Mrai
So this is it...