@faflak
I don't know which files you mean.
I downloaded and unzipped the file mentioned by Jurij in point 4 "R11AB029.S1_MSM8960_R3_S1Boot_1264_2289_Live_HWID6B50E1.SOFTWARE.rar".
Thouhgt that was enough.
"5. In S1tool choose S1 EMERGENCY mode, press Flash button, select Sony Xperia V LT25 boot firmware .sin_file_set file" Is'nt that the same file?