First of all, as it's my first post here, i would like to say big thanks for this great piece of software!
Now, the bug i've found.
After upgrading to this new 0.61, i've noticed that labels i apply (color or number ratings) disappear after restarting XnViewMP. It's not happening all the time, which is why i could not yet find a way to describe how to reproduce it. Seems to me that doing anything that makes the main window loose focus (like copy file to another folder, or using Open with > xncovert or for example) right after or right before rating or color labeling a file, makes it happen. I could not reproduce this in folders with very few files in them though.
I don't know actually what causes it but heres the things i do when it happens: Needs to have like 100+ photos in the folder, scroll down the browser and try to color label a file, then use open with -> xncovert or something else, or use "Copy to" to copy the file elsewhere, then restart XnViewMP. The file should've lost the color label. If not, try a few more times. If it's still not happening, then its something else causing it on my end, although it only started happening with the very latest version, 0.61, or at least thats when i started to notice it

Hopefully someone else can also reproduce this bug, it's very annoying, at least for me, as i have over 25k photos and i need color labels to remember what photos i've already used.
Thanks.
edit: i have Windows 8 Pro with all updates, Intel i5 2400 cpu, 8gb ram, 2x2tb hdd, XnViewMP 0.61 x64 and x86 both have this bug. Oh and my xnview database is on the 2nd hard drive, xnview is on the 1st.