Originally Posted by ChrisSlicks

If it is truly fully engaged in 1st (you feel the positive click) then there is something wrong, but more than likely it never fully engaged in the first place.

The Reverse to 1st move may occasionally require a double clutch, i.e. shift to neutral and let the clutch out, then clutch in and select 1st. The reason this happens is because the input shaft stops spinning fairly quickly, and R to 1st is the longest shift and takes your hand more time to get over there. The other alternative is to select 1st while still slightly rolling backwards.