The "Trailing Stop" feature attempts to "lock in" profit and to keep locking in more as the market keeps moving in your favour.

It works in the following way:

The bot will place all new sell orders a couple of percent higher than "normal". With "normal" being the price where it "normally" would have been given your configured minimum trade percentage.
If the market price has risen to above the "normal" price plus a small amount (usually less than 0.1%), then the higher-up limit order is replaced by a stop loss limit order at the "normal" price.
If the market keeps moving in your favour, then the stop loss limit order will be "lifted" as much as possible, keeping some distance to it (usually 0.1-1%) as "wiggle space". This is the "trailing" part of it all.
If the market keeps moving in your favour and the current market price exceeds the "normal" prices of any other open higher-up limit orders, then these will be cancelled and their quantities will be added to the trailing sell limit order.

About risks:

There is some loss in efficiency as the minimum trade price is effectively increased by a small amount (usually less than 0.1%)
There is also some efficiency loss because the code may be just too late to drop the limit sell and the market has moved already to your disadvantage.
In rare cases, the market price just "falls through" the stop loss limit order too fast for it to be triggered and the coin does not get sold at that moment.