move object using float instead of vector3 (question)

[gamedivision]

i have an object moving forward on the z axis continuously,when i swipe up the object moves up by 5 when i swipe down the object moves down 5,its locked only to 3 positions middle which is zero,plus 5 up minus 5 down,the problem i have is every move position only registers a vector 3 so when i swipe it wants to move to the 3 variables x,y,z instead of just plus 5 on the x axis,maybe ive missed something obvious or not but if anyone has an answer i'd appreciate it thank you.

[gamedivision]

I used the itween move add but it's not accurate at all,I tell it to move 5 and it moves 4.996 then moving back to zero it moves to 0.1123,I have a send event after the move, to wait .5 sec in case it's rushing through.

[gamedivision]

just a bump and a question as to why isn't iTween Move Add absolute,i have a send event to delay the movement and give it enough time to move but it isn't accurate in any way shape or form