So any idea why my wallet balance went from 55+ MFLAP to 0.00013555709161 MFLAP.
All the transactions that add up to the 55+ show up in the ledger

Actually, my balance is 0, the unconfirmed balance is 0.00013555709161

Also, part of block 700779 appears to be a POS transaction to me for 398,608.56228901 FLAP, which doesn't show up in the ledger or (obviously) my balances...
https://chainz.cryptoid.info/flap/block.dws?700779.htmyou are reading the block explorer wrong. the first transaction is Generation + fees (0 coins), the second transaction is what you staked
it looks like you staked 10 flap and made a profit of 0.00549315 FLAP which will be added to your balance one the staking blokc matures.
the other two transactions were people just sending coins on the chain to other wallets. they have nothing to do with your wallet and you wont gain coins from them, you just processed their transactions.
edit: did you add rescan=1 to your config file?
Rescanning now

edit: BTW, the first of the other two transactions are all from addresses in my wallet to the POS address in my wallet (and the other 0.88 flap to someone else). I didn't send any of those, I haven't sent anything in months...
Rescan finished, no change to balances

edit 2: Actually I sent menlatin a test transaction on 9/10
Status: 0/unconfirmed
Date: 9/10/2015 18:12
To: menlatin FUQer2xzYLa9k1Ww7B6hmaSvi4huAgEuat
Debit: -1.00 FLAP
Transaction fee: -0.002 FLAP
Net amount: -1.002 FLAP
Transaction ID: 59912ee770fcb96beaf6e8a836e028fe41354a5b9139a23bf4a500a388988116