Wrenkins I am here!!!! and am ready and willing to help Tia.
So hello Tia, all is not lost with your dress stand. First of all you need to close this right down to the smallest it will go and thus this will stop any wadding etc. from falling through. Next may I suggest you try and get some stockingette from Halfords, they come in two sizes a smallish amount and a huge great roll. The smaller one will be sufficient as this is going to be used to hold the wadding in place. Next do you have a particular garment that fits you well or is in fact beginning to strain over certain parts of your body? Are you prepared to sacrifice this for the time being?
So you will need to have accurate measurements taken, in particular from mid shoulder to the bust point, and across the upper chest - so armhole to armhole. Do you also have a bra that you are willing to donate to your dress stand, one that is right for you, gives you support and shape.
So things you will need are stockingette, plenty of thick wadding, the polyester type that is all lofty not the American batting, some really thick string of curtain weights, the thicker the better - I got mine from Merrick and Day up in Lincolnshire v(this is my own method for marking CF, CB, Shoulders, Underarm seam, Princess Seams). and some old M&S ribbed Thermal vests, or ribbed T shirts.
So I presume you know the areas which are going to need padding out. I literally wrapped the wadding around my stand, sometimes this was several layers, and this is held in place by stockingette. (Now to be honest with you I was wrapped a good few years ago now, and this initial wadding was to stop the wrapped duplicate of me from wobbling on a much smaller and closed up stand. somewhere in the middle of mine is a dry cleaners polythene bag, so I can easily slip my duplicate off if I want to. I have also used some old, and I mean old and tatty Marks and Spencer's Men's thermal vests, one on top of another and some have wadding inserted between the layers as I have put on a colossal amount of weight since I was wrapped. These M&S vests are long and ribbed, and the ribbing helps to show where the CB and CF are, get this straight and then the top one has the string of curtain weights sewn on and thus I can feel where it is when working with the stand as you cannot see through fabric generally.) So back to wrapping the wadding around in order to try and replicate the size and shape of you. Once you are getting near to the size you are put the bra on and get it positioned so it is giving you the same measurement mid shoulder to bust point, and then start stuffing the bra as much as you can to replicate your bust, try and make it as hard as you can. If you haven't got any ribbed T shirts or vests, then the stockingette will have to do but it will not be easy to see the crucial CB and CF lines. I have found that I can get stuffing in between the M&S vests and poke it to where I want it via the armhole, and I have just unearthed my cooking chop sticks which are quite thick, and a brand new wooden spatula to try and get into a smallish space via the armholes. Now once I was reasonably happy with the amount of wadding and vests on and had my curtain weights sewn in place, I then tried on one of my toiles that I had been making recently as I knew that this fitted me. This toile is a shoulder princess line that I have been messing about with for ages trying to get this just right for my particular shape, very large bust and a very large egg shaped abdomen. I then pinned the front together and positioned this over the CF ridge that I could feel, did the same with the CB, and then I could see where else I needed to push in more wadding (I still need to push in some more in certain places.) This toile is just about straining on the stand which is what I wanted - I know the toile is a good fit on me and I feel comfortable in it, so my idea is that if it is straining on the stand I can pin tightly into her when fitting and this will ensure I have my ease - so I can move and breathe.
Now one advantage of the string of curtain weights, I have an assortment of funny little things fastened to the dangling ends and these act like a plumb weight and keeps the string straight so again I can see from underneath where the lines are.
Now trying to pad your own stand out is not going to be a five minute job, it may take many days or weeks, and by continually measuring yourself and then where you are on the stand until you get enough wadding where you need it and get this secure. (I just raided initially my husband's old M&S vests, may be five or so first time around, then I found I liked wearing these M&S vests myself they are long and come down over my rear and really keep the cold out, only I did not like the highish round neck, so I doctored these to suit me by carefully taking of the originally neckband, cutting this in half lengthwise, and then cutting the vest neckline down by 5/8" and applying a much narrower neckband so mine look like ladies scooped neck T shirts. I cannot say how many I know have on my stand, but there are a lot plus the wadding and all of this has given a lovely smooth surface that I can pin into very tightly. The vests are all ribbed, some slightly different in the ribbing, but they are ribbed, and it is so easy to pull them into place to get a straight CB and CF line.)
I also have a reasonably chunky chain necklace around the neck - this is to show where I want a jewelled neckline to be.
Now just recently I was pinning tissue onto mine, I had already drawn on the tissue the CF lines, where I like my side seams (they have to hang straight), the beginnings of the lower armhole and the beginnings of the shoulder seam, the neck line, so with the tissue pinned in place at CF, CB, side seams and at the neck edge of the shoulder, I then started smoothing the tissue paper across the upper chest towards the armhole, and sort of stopping mid shoulder line, and then smoothing again from the armhole and a natural wave of tissue just formed for a shoulder dart aimed at the bust point, I then pinned this in place and it looked good. I then turned my attention to the underarm dart and did the same and the wave of surplus tissue just fell in to place, and it astounded me at how easy that had been. I am now in the throes of this tissue being the pattern for a summer robe - I have the darts stitched in place and again placed on the stand and it looks right so I am pleased.
I hope that this has encouraged you to have a go, and please feel free to come back to me for more help. Dare I ask whereabouts you are in the UK, you never know someone else on TSP may live near you and could help.
Good luck - and thank you Wrenkins for singing my praises - I am still waiting for that extremely loud yell from over the water!!!!!!!!!!