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First of all the thumbs are still unsharp - better than before but still not as it should be. It is also interesting that the cover thumbs are working well - only picture thumbs are blurry.
On the other hand I ordered especially your template Socialize to avoid such a design issue - it seems that both products are not working well together.
As I also submitted with my other tickets the functions, look & feel of release 4 are 3 major steps back compared to 3.1.0.6 (wrong sort order, pictures cannot be rearranged anymore and now the sharpness of the thumbs).
All of them needs to be fixed asap - otherwise your clients will get the impression, that you promise huge improvements from R3 to R4 but the reality is reversed
#1 for thumbnails we cant help you too much because this issue caused by responsive issue (as designed), the thumbs orignal size is 128x128px and since your main content is wide so the thumbs will follow it, and the thumbs will be 212x212px, to avoid it so I suggest you put module on the sidebar, so the thumbs will be better
#2 sort issue will be fixed soon I will let you know once the dev fix it.