I think the going concern language is pretty standard in situations with developmental companies.  We find ourselves in familiar territory, so I'm not alarmed by that.

I see the warrants very differently than many here, apparently. 

First, the .75 warrants had no effect on the share price based on selling or buying shares by the holders thereof.  The effect it had was to juice the share price up (temporarily, of course) when the first extension was announced.  I believe it was done because the company really thought the Sanan deal would boost the price up sufficiently for the holders to exercise, and, of course, the announcement itself made many here believe it was a done deal.

Second, the shares/warrants potentially springing from the convertible debenture - that debenture was a great thing for those who could afford to get in.  A big opportunity to cut one's risk in this investment by selling some stock and using the money to buy the debenture.  Few saw it that way.  Greed is difficult to overcome.

Third, the .52 warrants, an albatross left hanging around us from the "worst offering of all time" - I continue to be flummoxed by those that say the holders thereof are pinning the share price near fifty cents.  I'm also puzzled about the thoughts that somehow the .52 warrant holders wanted the .75 warrants to evaporate, and that once they did, the share price would be "allowed" to rise.  If I had .52 warrants, I would like nothing better than for the price to soar.  There's no reason to hold the price around the exercise price.  Sure, I can see those holders enjoying the occasional spike to .62, and then sell short there, knowing they can always cover if the price doesn't come back down (like every other time).  But you can't sell that many short, cuz the thin market for Poet shares will allow only the most nimble of those holders to actually make a decent profit.