first off, have you tried testing the return value of AppActivate? It will tell you whether it worked or not.
 
Also, it can activate an app based on only part of the title so maybe WShell.AppActivate "Evo" would work?
 
And, lastly, does typing X really do much of anything in Evo? Why send x?

This little script will give the focus to evo, then open a sales order. getting there!!
 
 
Dim WShell  
Set WShell = CreateObject("WScript.Shell")  
WShell.AppActivate "Evo ~ ERP"
WScript.Sleep 500
WShell.sendkeys "% x"
 
 
WShell.SendKeys "%"
WShell.SendKeys "M"
WScript.Sleep 50
WShell.SendKeys "M"
WScript.Sleep 50
WShell.SendKeys "O"
WScript.Sleep 50
WShell.sendkeys "{ENTER}"
WScript.Sleep 1000
WShell.sendkeys "{F2}"
WScript.Sleep 50
WShell.sendkeys "35324"
WShell.sendkeys "{ENTER}"
WScript.Sleep 50
WShell.sendkeys "{ENTER}"