Is there another way to access the pdf version of my current year tax return forms before filing? I can't view my forms during the final check stage before filing.

I just needed to switch from Firefox to Chrome to be able to see them. I was never able to leave from the "Preparing Your Documents" page while I was on Firefox.

What way did you try?
You can (and should) preview your return.   Go to TAX TOOLS on the Left side.
(You might have to click a little to the left of "Tax Tools" to make it open

Then click on TOOLS
Then View Tax Summary (first link in the Tools Center box)
Then Preview My 1040 on the Left side again

Then Click Back near the top of your screen to exit the preview screen.

https://ttlc.intuit.com/questions/1901539-how-do-i-preview-my-turbotax-online-return-before-filing

Pay the preparation fee and register -- then you can see your entire return. 

Visit the Print Center to get the ball rolling.

Always a good idea to review a paper copy of your final return carefully before e-Filing.