Hi Rob,
Is there a limit on the number, frequency or daily amount of stakes?
I performed 3 during the last 24 hours (all registered), and trying a 4th one, BBP-LTC stake. Dry run gives no errors, but when I submit for real I get "Transaction signature failed. Unable to Create UTXO Stake Transaction." ?
There is no limit, but the current wallet requires coins to be > .01 days old. One other thing is, I noticed the wallet may possibly spend a transaction that is not yet locked to pay the 1 bbp fee. I am currently working on a solution for that for a leisure.
In the mean time, try this: exec bankroll 10 10
This gives you an extra 10 transactions that are only 10 bbp.
Then after 3 deep try again.
All, I will answer asap, Im doing a little testing to provide better answers.

5800 BBP