Hello. I have just restored and painted my sash windows, having applied the top coat of Sandtex Gloss this morning. I now need advice on the best product that will fill the EXTERIOR gaps between the various wood trim and the brick wall, and between wood and wood - where various bits have gaps. It need to be white, stay white (not yellow), water and weather proof, not crack over time, and from a catridge. As well as filling the gaps it needs to stick to gloss paint which is toward the surface of the application. I've looked online at Screwfix and Toolstation but everything I look at has a armful of 1* reviews saying "rubbish". Ideally you have experience and can recommend something having used it and it was great and years down the line it is still good and it is still on the market! Wishful thinking? Thanks.