UE4 freeze after double clicking or editing constant 3 vectors

HI Warner -

You should not need to have Visual Installed but the runtime error you are getting has to be associated with an error in the Redistributables or the dotNET Framework. Take a look at this Microsoft Answer article and see if you can follow it to a solution,

http://answers.microsoft.com/en-us/windows/forum/windows_7-windows_programs/runtime-error-p6025-pure-virtual-function-call-on/89e10d2f-b949-e011-8dfc-68b599b31bf5?auth=1