I don't understand your first question...
You define/set/initiate a variable earlier on, then use the conditional to check it.... To set it in QDK look in the variable thingy and there's "set string variable" or something...
Your second part, check if a variable is 'more than' 5...
In QDK, variable up the top, "more than" in the middle (I believe) and 5 in the bottom box... Oh, and it's check a variable against a certain value or something....
Raw code is as follows:
1)
set string <variable; value>
2)
if (%variablename% > 5 ) then {
msg <Decription message>
} else {
msg <Lower level description message or other conditionals>
}