Note that the web page is not enlarged like it was in step 3. In fact, the web page appears even larger.
Indeed, seems to be happening when built against revived QtWebKit, it seems that zoom value is set as base value (setting 100% makes it look like if zoom was set to value from previous session) and then applied again.
About images issue, apparently QtWebKit build for Windows 32 bit has again issues with JPEG rendering. :-/
For now I can only suggest to stick to xp build.
BTW, this topic is a mess, please use one topic per issue (unless they are related).
I'll close it before end of January, please confirm reported issues that weren't fixed yet.