I had a massive problem with leg sores and awful nappy rash once teething wee started.
We've finally settled on huge fleece squares which flap out of the side of the nappy and hold the wee away from her leg meaning that nothing rubs where she is wet. I'm using large sandies with the leg poppers on the loosest setting - and the waist on the smallest as she's also skinny
The best cream I've found for us is the boot sensitive baby one - it's lanolin based and seems to be a a good combination of moisturising and barrier.
Then we use wool over the top, as no tight seams - although I have had a problem with a pair of dragon flair shorties - the rib on the leg irritates her, so we've had to stop using them atm.
You might find you're no better with sposies - we thought we'd try them and the leg elastic irritates her after about 12 hours.
The fleece isn't pretty but it does seem to do the job for us. Is your DD allergic to fleece? I did consider fastening the fleece like a terry, which could be your best option with your DDs exploding poo.
- I know how awful it can be - I was beginning to despair of ever managing to get her skin healed up