I could kick myself, I thought coins were sent out LIFO (2 days before stake, too). Now I am investigating MW to hand PoS as you suggested, but I am trying to understand how it works. Are wallets loaded with loadwallet pushed onto a stack such that the gui/commands operate on the top wallet?
Also, is there a command to transfer coin between wallets without being taxed?
To use the gui, you need at least 1.2.1.8. I should have an updated pre-release ready this weekend. Which will fix a few of the issues in 1.2.1.8. But still not full release yet.
If you are on 1.2.1.5 you have only rpccommands for MW. These work good for me. RPC commands default to the main wallet (wallet.dat) Unless you use the rpccommand usewallet <walletname> then the normal command.
Please review this page for additional help.
https://bitcointalk.org/index.php?topic=303749.msg3413502#msg3413502 with rpc commands.
As far as loosing stake. I also do plan to get ACC into the wallet next. But that is a bit far off.