Looks good H. I don't think you'll need much in the way of filler, as the joints look fairly close. I'd use a mixture of talcum powder and Future, run into the joints, then sanded when hard. Mix the stuff so that it looks like porridge, and you should be set to go. Run it into the joints, sparingly, until they are filled. You might need to let the first lot set, which only takes about 30 minuts, before adding more. use an old brush or a cocktail stick to apply the 'porridge'. Much easier and not as messy as that sloppy putty in a tube - and a darned sight cheaper too!