I am aware that the hatch tool fails in 'some' situations, usually if shapes are rather complex with ellipses and/or splines (such as exploded or projected texts).
I'm relying on Qt for this functionality, so it's unlikely that this problem can be fixed on the QCAD side.
As a workaround it sometimes helps to break down the shape into several, smaller shapes. In the case of exploded or projected texts, use the hatch tool on one or a few individual letters at once instead of the whole text.

Okay thank you Andrew for spending your time to look at this for me, much appreciated. I will take your advice and try to break things down a little and see how that goes.

Thanks again.

Okay, I split the drawing into four and successfully projected and hatched it ;). So yes it is doable -but takes a little time.