EDIT: it is SOLVED - I've had it running on another PC, which I was not aware of. If kept playing same map, with just gold increasing. Sorry for messing up.
For the 3rd time, I got "resetted" to some really early stage of my game. For the 1st time, I thought it was due to some Kong issues. For the2nd, I wrote a bug report (yesterday). Today, I got back to the very same map, with very same monster setup... as in previous 2 times. What IS strange, I click the save button, game says it was saved. I refresh the page - game loads fine, exactly where I left few second before. BUT closing the browser and launching game again, after few hours ... gets me back to the same point in game time - meaning I lose ALL the progress. All my time spent on clicking, on drawing cards, casting spells, reseraching and developing ... this is annoying. Going from wave 240+ back to 60+ . I liked the game, but the "back-in-time" makes playing it pointless. Sadly.
 "Idle Monster TD"){kind=icon}
 "Hook"){kind=icon}