If you already got the previous Warcraft Version Switcher, you only need to add the 1.26a.zip package and put it on your WVS folder
Download:
http://gotupload.com/zgtg51njs3xi/dota360.com_TFT_Version_1.26a.zip.html (32.4MB)
http://www.mediafire.com/?vzmzzv1cbqzwfql