This is all unravelling.
Firstly my diagram was just a generic one to show Eric how RGB amps fit into the general scheme of running LED strips - it has absolutely nothing to do with your requirements, your design, or any products you may have identified or bought so far.
Secondly, and most importantly, you seem to be adopting a pretty scattergun approach to asking questions as and when they occur to you, which isn't a very good way of advancing you from the position you are currently in which is, let's face it, one of not really knowing enough about how LED strips are constructed, how they are driven and how they are controlled. You would be better off contacting major suppliers (proper UK resident companies) and asking them if they have any comprehensive guides to how their products are used so that you can buy the appropriate stuff. They might even help out if you tell them what you want - how many strips, how long, where, how far apart in relation to each other, of far away from where you can put the drivers etc, what sort of controls you want and so on. For example you've bought constant voltage power supplies rather than constant current LED drivers. Is that what your LED strips want, or will want? You've bought power supplies which need to be used indoors, and inside another case, probably with forced air cooling. So how will you use those to power external lights? Remember that voltage drop is much more of a problem at 12V than it is at 230V but you may not be able to attach large cables if you need to run them over some distance.
Thirdly, scouring Amazon and eBay for the cheapest Chinese made junk you can find is likely to be a recipe for failure, particularly when trying to integrate products from different manufacturers.