3...we have already a big name partner or possibly the future purchaser of our Denselight subsidiary to back us up till september.

I have thought about this scenario too, but I think it puts too much faith in the Denselight buyer and wouldn't be a good decision from a business standpoint.  The BATNA in case 3 would likely be scenario 4 and being salvaged for pennies.  The denselight buyer could even strategically bring us to option 4 in an arrangement such as this. It would be too risky, in my opinion.

Hopefully we're closer to option 2 with or without the NDA, and option 1 is our worst case scenario. If interest is as good as we are led to believe I would prefer a cash raise by any means versus pumping the brakes on progress in option 1, assuming Suresh and co. can negotiate a reasonable value.