This may be related to several other securities concerns.
When the same security is traded in multiple accounts and there are multiple splits over the history, sometimes the current number of shares in one account is incorrect.
Specifically, I have Abbott Laboratories (ABT) in 4 different accounts. After importing all accounts, one account had too many shares. There were two 1991 transactions before the May 29, 1992 split that appeared to be split one too many times. I deleted one of the transactions, re-entered it, and the current number of shares increased as if it was split two too many times. Looking in the history for ABT in each account showed only three splits, May 31, 1990, May 29, 1992, and May 29, 1998.
Further, looking at the security history for ABT on the home page, only three splits appear, but the first two have security prices of 1 instead of the Pre or Post split price, but the 1998 split had the Post split price shown. Also, transactions were listed for all of the accounts, but the account name for each transaction was not shown.
Lastly, I found that I could edit the splits simply by placing the curser in the box and typing, without having to enable an edit permission or save change permission.
I am currently using build 518 on a Windows XP platform.