casement window problem

The other day, I was on a mission to seal up some drafts and prevent heat loss.
I noticed that the casement window in the basement was just single pain glass.
I removed the screen and planned on cutting to size a piece of poly-carbonate storm window to replace the screen with.
Before I did this, I scraped away the flaking paint, sanded and prime the surface and then finished it with an exterior latex based paint.
I waited a day for this to dry and then installed the poly window and siliconed in place. Today I checked the window to see if I sealed it up OK and noticed that there is now fogging/moisture sticking to the poly window.
I figured a dead air space would help the R-value of the single pain glass window but, don't want moisture between the pains.
Is this a temporary condition from the paint still curing or should I expect this to be the case all winter long.
For now, I have the casement window open to the inside trying to help the silicon, paint and moisture dry out. I even sprinkled some descicant silica in the window to absorb some of the moisture but, in the long run, I want a moisture free condition.
Did I do something wrong in my efforts to help retain heat and ward out the cold?

Hmmm - Do you need the window for light? Its a basement casement window, I suspect in an opening in the foundation. I would just fill up the foundation cavity with some fiberglass bats fit snugly in the space. That would give you the best insulation.

If you really do need it to be aesthetically pleasing. I have seen some new caulk from DAP that is 'temporary' that can seal up all the drafts when the window is closed and peel off in the summer when you want to open the window. That may help.

Yes it's a basement casement window that I want light from.
This is why I didn't place insulation in it.
I caulked the poly in place so that I could slice it with a razor knife next spring and get the poly out.
I was going to seal the casement frame itself but thought it would be a better R-value to have a dead air space between the poly and the glass. The poly was installed in place of the screen on the outside. I used silicone that goes on white and turns clear when cured but, I see that some of it is still white.
Really kinda bummed at the results. Maybe I have to make some breather holes in the seam or the poly? Maybe this condensation confirms heat loss through the casement window?