Thank you so much to Colin, a skilled carpenter who put our filler and chip repair kit to the test on his cream Aga range cooker.
Here is a little video showing how it can be done!
"The filler is very easy to use,takes a bit of time to set hard (the instructions state 4 hours, in the real world I would leave it overnight) but when set is rock hard and there is plenty of it, its basically a 2 part plasticine style filler that is mixed by hand and fills very fine/thin holes no problem, and the colour touch up paint is very easy to use and the colour match (I used cream) was perfect and very hard to see where filled/painted. I am a carpenter and do this type of filling regularly but it's very easy to use, just make sure you prepare the area well, take time to carefully sand down correctly and apply the paint in two to 3 thinner coats." Colin