As for the price action there were plenty of warning signs. As...

As for the price action there were plenty of warning signs.
As simple as that : as soon as stop loss price level is hit you SELL.

I did that, lost some money, but at least saved the rest.

So 3 lesson for the future (and they are well known basics in investing) from this company is:
- never buy stock of the company with BAD or questionable management
- avoid buying stocks when their price is falling
- sell when the stop loss is hit (do not move the stop loss price lower and lower, because eventually it might hit 0)