There are a few additions I'd like to make to your post.
1) The major health factor with mineral wool is not the skin irritation, (Although that in itself is bad enough) but the fact that the fibres can cause irreparable damage to your respiratory system. For this purpose I must add that it is advisable , indeed, essential that you wear a face mask during ANY work with this material. I also recommend using disposable boiler suits with elasticised limb closures and a Hood.
2) The Spray application of the liquid is far more efficient and effective, as well as safer. As I suggested, use an old plant sprayer... such as those you get for greenfly treatment of roses , but ensure they are cleaned thoroughly before use... (and After if you intend to make more )
3) The Corner traps would almost certainly be more effectively used diagonally across the corners rather than directly in the corner. The air gap will lower the bottom of the effective frequency band and increase efficiency. Mount One on top of another giving 2 meters of diagonal corner trapping rather than in front of each other.
4) Tape isn't a terribly effective fixative, spray contact adhesive, applied to rear of the AMW sheet, and front of the Board is more effective, and once the material is wrapped around, is better at preventing sag over the long term.
5) Fixing the 100mm stuff to a board is also advisable, as they will sag in the long term without some support.
Also, this would enable use of these in the wall to ceiling vertices as well as wall to wall.
In general I would fit one diagonally to the centre of each wall to ceiling join, and two upright diagonally in each vertical corner.
Fitting them diagonally is actually quite easy once you have the knack of it, but is most definitely a two man job, as it's impossible to support the weight in the correct position AND fit the supports.
if you affix 4 suitably strong Eye bolts to the supporting board, and 2 to the the wall (as tight into the corner as possible) , a few inches in from the end of a panel, then you can use steel cord or chain link to suspend the panel, pulling it tight into the corner at 45 degrees diagonally across it. This basic method can be applied to both the wall to wall joins and ceiling to wall joins.
you may find you need to use a third central one if the wall construction is less than solid.... in the absence of available direct fixing to timber frame or masonry wall, proper load spreading wall inserts should be used in the case of partition walls and the typical internal room within room wall construction.
6) RW6 is NOT the densest available stuff..... AMW is available in densities up to about 120KG/m^3
7) Bearing in Mind this is part of my "day job" I hope you'll understand when I don't give away every single trick of the trade
But this should be sufficient to avoid unfunny disasters in the DIY sector !
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