I was having the same issue and I think I identified the cause.
I had "All in" ticked when I first started the bot, and it bought for whatever amount was the 90% of my total. Then I simply left it to do its thing... just that yeah, it was not selling despite lots of Sell signals being displayed. Finally today I had the 'genius' idea of unticking "All in" and ticking it again, and voila, instant sale.
So I believe there is a bug when calculating the All in amount sometimes, maybe after the buy in. Perhaps an automatic recalculation of this amount every certain time/intervals could help prevent any issues here.
I don't know exactly what caused it, but with 'All in' ticked it should never try to sell more coins than you have unless you manually change the value, and I believe that's what was holding back my bot from selling (that thing Stephan is working on should be helpful to identify these issues if it includes things like that "Sell failed because the amount of coins to sell is bigger than what you have" or something similar).
Does yours work properly after you tick/untick the All In? I noticed that after my initial Buy (with Coins position set to Sold first of course), my wallet didn't update. Then I clicked All In / unclicked it, and it updated the wallet. I'm waiting to see if there is a successful sell / buy etc. cycle after this.
Edit: Doesn't work on mine. It seems that after each unique buy or sell, the wallet fails to update correctly after the event. I'm guessing that's why my debug log is lined with actions, but no corresponding trade unless I manually reset the wallet using this "All-in" hack. As a result, my bot only ever carries out a single action (it seems).