pull those sell orders, put it back in the premine wallet and burn it all... That's the only legitimate way your going to start winning people over. Better push a full release and use that money to pay for some positive press releases.
I have seen this happen many times and it all ends the same way a dead coin. We thought we could trust that was locked away( premine) and we would be informed of any movements.
You also said that you spent to much time and money to let this project fail.
Best would be for people to rather put their buy orders at 100-300 for in case there is another dump. In light of this dump (despite assurances that a large dump will not be done) it means the whole coin supply is in play as the remaining 7.4m could also be dumped at any time. The average price for a 10m coin is 60-300.
If the project's interest came first the best possible prices have to be realized when premine coins are sold. A better way to handle it would have been:
1. Guys, I have no choice and need money for the project so I am going to sell 1.5m coins in the market on date X , please get your buy orders ready.
2. Guys, I talked to a private investor/(s) that wants to take up 1.5m coins for X BTC (or X chunks of Y coins @ Z BTC). Is this OK or is there someone else that want to pay more for the coins.
3. Guys, I have no choice and need money for the project. Please PM me an offer for X number of coins up to 1.5m coins and I will sell down the offers until the 1.5m is up taking into account that higher market buy orders will be honored first price wise side by side in the mix.