BonsaiMon

Jim,
I see a couple situations which don't help this problem..
kitty litter breaks down quickly, absorbs more than other high fired clay soil additives. put a small amount in a cup of water and let it sit for a week or two and see what the consistency is.. i hope not but I feel you find it a slimmy clay muck.
What size hole is in the pot the maple is in?
It looks like a garden center planter. If it is the drainage hole is way to small. I have used some of these but have had to create more of a drainage hole then the single 1/2" hole they come with.
These two possible situations and the fertilizing may be the cause for the root rot.
I'd repot as advised making sure there is good drainage in the pot. Your mix sounds ok.. kinda?.. what is forest bark?
hope we are hitting on the cause of this malady..

__________________
peace,
tom stoute

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