Images N/A with SSL turned on

[Insink71]

sorry to jump onto an old thread, but I had a SSL security question with compressed images results. Does enabling HSTS screw with webpagetest.org's ability to test for such? I checked gzip, and I don't believe images are gzipped [on our server], but noticed https://teamblueridge.org's test results get N/A where another site like cyanogenmod.org gets such results. I can only guess it has to do with image headers, thus my question. Thanks for your time in advance.