Scale changes when applying curve modifier very annoying as sometimes it happen and sometime it doesn't (first curve is fine) i just want the cube to stay the same exact scale it has originally... i also apply both scale + rotation on both ... what can be done to fix it ?
If you've scaled your curve and applied its scale, the radius of its vertices is no longer 1. So select your curve, go in Edit mode, select all the vertices, and W > Set Curve Radius (value 1 by default, that's what you want, but you can change it on the bottom of the T panel), or in the Tools panel of your 3D view (displayed with T on the left of the 3D view) go in Tools > Curve Tools > Set Curve Radius and choose a value of 1.